Bus Conversion Magazine Bulletin Board

Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Kwajdiver on November 18, 2007, 07:53:04 AM



Title: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 18, 2007, 07:53:04 AM
Good Morning Guys,

I was all set to make a short run to the truck stop for fuel.  Press "D" and the tranny did not engage.  Tried to check the transmission fluid.  My dip stick looks shorter, than I remember.  I'm sure it's not going into the tranny.
Put about three quarts of fluid and still won't engage.

Do I need more fluid?  Didn't want to over fill it.


Bill
Still in Gulfport, Ms


Title: Re: MCI-9 Transmission won't engage
Post by: grantgoold on November 18, 2007, 08:05:04 AM
Have you checked to make sure that a signal is getting to the transmission when you push D. It could be a simple as the button is bad and a no contact situation exsists. Can you hear the tranny trying to shift gears from neutral?

If it worked fine before, I would check the electric signal first and be careful not to overfill the tranny.

Grant


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 18, 2007, 08:10:59 AM
The tranny is not trying to shift.  Tried both "D" and "R".  Last time this happen, it was just low transmission oil level.  Of course then I remember having a longer dip stick.  Believe my dip stick has broke off.

Will check the switches.

Thanks, Bill


Title: Re: MCI-9 Transmission won't engage
Post by: grantgoold on November 18, 2007, 08:26:03 AM
What's your plan retrieve the end of the stick? Drain, drop and search? Does you bus have a safety feature that will not allow shifting until the air is all the way to a safe zone. I cannot shift my bus until the air has exceeded 90 psi.

Keep us posted.

Grant


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 18, 2007, 08:29:17 AM
My dip stick is 23 inches long.  I need to someone to tell me if that is correct or not.  Seems like last time this happen, I added something like 5 quarts. 

My air is okay, I'm pumping up to 120psi.  Just added 2 more quarts, starting bus now,,, Will see.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: grantgoold on November 18, 2007, 08:45:59 AM
That seems about right. I thought mine was a bit short as well. Can you tell if the end broke off. Are the gradations still on the stick (add, full...) Hope the fluid works. Are you leaking that much?

Good luck!

Grant


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 18, 2007, 08:58:26 AM
Added two more quarts.  Still not working, I'm now sure it's not a fluid level problem.  My dip stick looks broke on the end, does not have any writing on it.

Going to pull the switch panel and see what I have there.

Bill



Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 18, 2007, 01:58:33 PM
The switch panel doesn't give up much information.  The buttons all work, but hard to tell about the electronics.

Any thoughts will help.....  I'm over my head,,, again    ???

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: grantgoold on November 18, 2007, 02:48:15 PM
Bill, can you determine where on the transmission the electronic signal goes to from the panel switch?  (Sorry, I have the traditional floor shifter)  If so, you can then have someone check to see if the signal is getting from the switch to the tranny. 

Does the panel switch have a fuse? You may want to check your repair manual and see if the unit has a fuse for the tranny.

Just some thoughts. Seems very odd that the tranny would just fail internally without some earlier indications.


Good luck!

Grant


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 18, 2007, 03:00:59 PM
Grant,

I don't find much in my manual on the tranny.  Shows how to change the filter, that's about it.  I was wondering about the a fuse.  Not a clue were one may be.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: makemineatwostroke on November 18, 2007, 03:18:15 PM
Bill, what is the model of your transmission and maybe i can help


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 18, 2007, 04:49:36 PM
It's an Allison Automatic, four forward, believe that makes it an HT740.  A 1983 MCI-9.

Thanks for the help,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: makemineatwostroke on November 18, 2007, 05:13:37 PM
Bill, on the drivers side on the transmission right above the pan it should have a tag with the model number.If your transmission is a HT 740 its probably a Stone Bennett shifter.let me know how deep your oil pan is and i will tell you how much of your dip stick should be down in the pan.But we need the model of the transmission to help.there should be a plug on the pan where you can check the safe level for the oil above where the dip stick tube is mounted to the pan.

Bill this sounds like a oring on the pickup tube being you had to put more oil the last time when it happen,its a 1.00 oring but cost 80.00 for the oil and a new gasket


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on November 18, 2007, 06:09:44 PM
What about setting the brakes and before the engine and trans get too hot  to dink with,  crawl into the RH engine service door and manually shift the trans into drive or reverse?  Have someone hold the service brakes maybe.  Even with an SB shifter, there's a linkage that can be moved.
Get the high idle off, and don't manually shift the transmission before the low air buzzer goes off.   You may not have enough brakes to hold the coach. 
If it goes into gear, the trans is OK and the Stone Bennett has issues.
Obviously, make sure that the bus cannot move when doing this sort of thing. 
I'd expect it'll shift.  If it was working when you shut it down, it'll very likely work now.
IMHO, the broken dipstick isn't worth going after until you're ready to service the transmission filter and change the oil.   The broken tip should lay on the bottom of the pan. 
It will not pass thru the pan filter. 
If manually shifting doesn't make the trans go into gear...bummer.  Major bummer!~
You don't have an ATEC (HT748) trans?  Could have been retrofitted?   Not likely, but possible.   Does your transmission push button control have round buttons or is it a square buttom touch pad with an Allison logo cast into the upper surface? 
Another way to ID the units is if you have a big bundle of wires going into the PAX side of the trans, it's an electronic unit, if you have a cylinder and shift linkage on the side of the trans, it's an HT740. 
Good luck, JR


 


Title: Re: MCI-9 Transmission won't engage
Post by: makemineatwostroke on November 18, 2007, 06:34:35 PM
Bill,there was another manufacture of a shifter also but i can not remember the name right now but it will come to me. If you do have a Stone Bennett air shifter that is not working 95% of the time the problem is caused by dirty air and can be a simple repair. look on the passenger side if you have a box 2in thick 4in wide and about 6in long with a rod in the center with wiring and 1 air line that will be a Stone Bennett shifter.Check it like JR said and if the shifter is not the problem i will tell you how to check the pressure and we will go from there


Title: Re: MCI-9 Transmission won't engage
Post by: captain ron on November 18, 2007, 07:19:36 PM
If it was an ATEC the red light would come on telling him "DO NOT SHIFT" and he would have told us that, so most likely not ATEC


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on November 18, 2007, 07:50:11 PM
Bill, can you post a pic of your shift selector and one of the curbside of your trans?
This will allow all of us to lead you in the right direction, once we know for sure what kind of unit you have in your coach.  8)


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on November 18, 2007, 07:50:22 PM
If it was an ATEC the red light would come on telling him "DO NOT SHIFT" and he would have told us that, so most likely not ATEC

Yep.  The red "do not shift" light would light...so long as the ATEC fuse (or 12V B+) wasn't interrupted for whatever reason.   
You are probably correct in assuming Bill has an HT740.  But hey...before enlightenment, I thought you had an MUI...based on the year model of your bus?   ???
A Stone-Bennett is an electric over air shifter...and I'd guess that either it's shifting electrically, but got the cruds...and stuck.   SBs can be a PITA when they age...just like me!   Moving it about may return it to a functional state..albeit for a short time...just like me!    ;) 
I like to make big SWAGs  when guessing at a problem!  ;D
Be interesting to see what's causing the non-shift thing.  Hope it ain't the transmission.

JR






Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 18, 2007, 07:56:19 PM
Guys,  I will crawl in the engine compartment in the morning, take requested photos and also look at the other items.

I had NO hint of trouble last time I move the bus.

Thanks for the help,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: makemineatwostroke on November 18, 2007, 08:08:50 PM
JR,what if we are all wrong and this guy has something like a ZF tranny   


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 19, 2007, 05:46:42 AM
The transmission is a HD 741 D. I see no shifter, no Bennett Box, and no air line.   I do see on the pass side a large connector, (control Cable) located just above the pan.
The control shifter located is on the right side of the driver seat.  The unit has square backlite buttons.  Has an Allison logo on it.

I've spray everything down and cleaned it.  If you still need photos, can do, after work.

As far as the dip stick, I'm guessing it doesn't have to go all the way into the oil pan.  Looks like the tube is connected near the bottom of the pan.   The tube would have the same level as the pan....  Still, will seek a new stick today.

Thanks for the help,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: makemineatwostroke on November 19, 2007, 06:10:49 AM
Bill, i will try and e mail you a trouble shooting guide for that transmission i hope you don't have a major problem because that transmission stopped production in 1997 and parts will most likely have to be aftermarket


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on November 19, 2007, 06:52:10 AM
Bill, you have an ATEC transmission. Allison electronically controlled transmission. They have been around since at least 1983.
Since you say you had no indicator lights, I would check to see if you blew the power fuse for ATEC.
It should be located in the battery compartment, in a seperate single fuse holder.ATEC is a 12 volt system.
When you first turn on your dash master switch, the "DO NOT SHIFT" light on the shift pad and "CHECK TRANS" light on dash should come on and go off in 2 seconds.This lets you know the system is powered up.
Let us know what you find.
Sammy  8)


Title: Re: MCI-9 Transmission won't engage
Post by: makemineatwostroke on November 19, 2007, 07:16:01 AM
Sammy i wasn't saying the ATEC went away but 741 and 755 left 10 years ago


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on November 19, 2007, 07:21:11 AM
Makemine, no disrepect was intended. I agree with you, it's old technology.I happen to have an Allison ATEC manual dated 1983. Just wanted to give folks an idea of how long it's been around.
Again - no disrespect was or is intended at all. My apologies to you if you were offended.
Sammy


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 19, 2007, 07:30:08 AM
The fuse, I do not believe is in the battery compartment.  Would have to be in the outside panel, driver side.  Isn't this system a 24vdc ?    Do not recall is "Do Not Shift" or any other warning light comes on.  I hit the start button and walk away, till the air builds up.   Will run home in a little while and look for the fuse and check the lights.

Thanks, Bill
1983  MCI-9


Title: Re: MCI-9 Transmission won't engage
Post by: makemineatwostroke on November 19, 2007, 07:45:28 AM
Sammy in no way did you offend me I am new to this board and when I post i leave out about half the info and think people should know what I was talking about.I enjoy your post because of the accurate info you provide for people


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 19, 2007, 07:48:05 AM
Okay guys, kiss and make up..... ;D

Back to my problem..... LOL

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: captain ron on November 19, 2007, 07:49:05 AM
The ATEC like a DDEC is a 12 volt system that gets it's power from the vanner equalizer above your batteries. There is an inline fuse on the back side of the panel that holds your disconnect switch.


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 19, 2007, 07:59:03 AM
Going home to check it now... Do you have a number that I can call you....?

Thanks,
Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 19, 2007, 08:44:41 AM
I do not see a fuse or circuit breaker in the battery compartment.

The MCI manual Page 7-24, states that coaches with ATEC transmissions should have a 40-amp circuit breaker.

Nowwwww,,,, I wonder where they put the damn thing.

Also,  when I started the bus.  No warning lights came on.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: captain ron on November 19, 2007, 09:07:10 AM
If nobody else is helping you via phone call me I might be able to help locate the fuse for you but not a lot more. I do have ATEC tranny though and I'm at the bus. 239-292-1750 Ron


Title: Re: MCI-9 Transmission won't engage, more
Post by: Kwajdiver on November 19, 2007, 02:17:55 PM
Okay, now were getting somewhere...

In the driver side second bay, behind a drop down panel, I found the Transmisson Control.   Found a 24/12 VDC Converter, an Electronic Control Unit (ECU), three relays, (Check Transmission, Retarder, Reverse), three 5 amp fuses (all check okay with an ohm meter), a test light, test switch, (which doesn't seem to lite the test light), an hour meter, and a 5 stud block, with black wires on 1,2,3.

The first thing I need to determine is do I in fact have 12 vdc out of the converter.  Does anyone have a drawing of this, or the same unit?

Help,,,,, over my head, still...

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 19, 2007, 02:23:51 PM
Then I start the engine   ::)

I now have that red light on (still in the bay), 26vdc on all 1,2,3 on the 5 stud block.  I believe I have 12 vdc out of the converter.

How do I test the ECU?

Do I see a light at the end of the tunnel?

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on November 19, 2007, 06:33:56 PM
Bill, make sure you have 12 volt output on terminals 4,5,6,7 of the 24 volt converter.
You are doing a fine job so far. You'll get to the end of the tunnel.
Here's a breakdown of what these wires do:
Term 4 - 12v for ECU memory
Term 5 - 12v Battery power to ECU
Term 6 - 12v Battery power to ECU and shift selector
Term 7 - 12v Battery power (switched) and to Term H of the data connector.
The Data Connector might be at bottom of shift tower, might have a spring loaded metal cover on it. This is where a ProLink will hook up.
Let us know your results.  8)




Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 19, 2007, 06:38:49 PM
Sammy,

Can you give me the voltages on the ECU connector. Would be easier to get probes on.

Thanks for help,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on November 19, 2007, 07:35:16 PM
Bill, has any work been done recently around the shift tower, or bus wiring? What did you work on from the time you parked the coach and the time you tried to move it?   
I've seen the cannon plugs fall out of the backside of the shift pad.  Also seen wiring disturbed and fail. It was about to fail anyway.   
That would not affect the voltage readings.  But a CEL for the transmission would set. 
If you are not getting a transmission light, something's not powered up. 
Sammy's going to get you fixed up!   
And Ron, Vanner recommends that nothing but the battery leads be attached to the Vanner terminals.  I doubt any harm would come from attaching leads to the Vanner, but it may confuse the Vanner causing an  overcharge condition on one of your batteries (the rear battery).   
The 12V source for your transmission is the center 12V post on the rear battery.  Same for the 12V headlight backup lead.
Sammy, if you're passing out your phone number I'd love to have it!!  You one smart guy!  My bus is gonna crap somewhere one of these days and I want someone that knows some  $#i+!    You know your stuff.  Very nice! 
Bill, feel free to call if you have a question regarding anything other than that ATEC transmission. I'll talk about that too, but I'm not versed on the unit as Sammy is.  I do ex-NJTs and that's all I understand.  DDEC and ATEC 748s.   That's it. 
I'd definitely want to know what fixes this thing.   :D
 
JR
704 650 0235 anytime. 


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on November 19, 2007, 07:38:41 PM
Bill, try this....
J2 connector (black one) of trans ECU:
Pin 3 -  wire 203 - 12v memory - fed by term 4 of converter - might be a red wire
Pin 8 - wire 208 - 12v battery power - fed by term 5 of converter - might be a Blk/Grn wire
Pin L - wire223a - 12v battery power - fed by term 6 of converter - might be a grey/Red wire
Pin 2 - wire 202a - 12v switched battery power - fed by term 7 of converter - might be a Red/White wire
I do not have a electrical diagram of your coach to see how Allison wiring integrates into it.
For instance: There is a switched 24v source of power going to Fuse 3 - a 5 amp fuse or breaker.
It then goes into the 24 v converter on term 3 - a 24v input.
It is the only switched 24v input - as per the Allison diagram.
Maybe it becomes the 12v output on term 7 of the converter - a switched 12v output.
Maybe it becomes wire 202a, on pin 2 of the J2 connector of the ECU, telling the ECU to turn on.
Diagram shows no internal wiring of 24v converter.
Let me know if you need a picture of J2 and pin locations.
Sammy  8)



Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on November 19, 2007, 07:42:45 PM
Sorry about all these  postings.  But Bill, do you have a kneeling valve on your bus?  Its a switch in the LH side dash on top.  Next to the air lock switch.  If you have a kneeler, the trans won't shift at all with the kneeling function is deployed.  
Just another thought!  
JR



Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 19, 2007, 08:27:15 PM
JR,

Don't believe I have a kneeling switch, don't see anything like that.  Is there anything else that would prevent the transmission from engaging?

I do have a Step switch left of the dash. It is disconnected.

Not sure if this is connected to the problem, but I may not have Fast Idle anymore.  Really haven't been too concern with that, being as I don't seem to be going anywhere.   :'(

Thanks for all the help, everyone,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: captain ron on November 19, 2007, 08:36:49 PM
Do you have a DDEC engine? And does your motor stay running for a reasonable amount of time? The reason I'm asking is when you have a fault code the DDEC will not let the fast idle work and then will shut down your engine, might take ten minutes. I don't know if it works the same for your ATEC. You may want to get someone with a hand reader to check your tranny for fault codes.


Title: Re: MCI-9 Transmission won't engage
Post by: niles500 on November 19, 2007, 10:53:18 PM
Before I get flamed - just as a pleasant reminder - disconnect the ATEC from its power source for a 10 minute period - when reconnected shift to neutral - if you can't get a neutral indication see ATEC trouble shooting  guide - HTH


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 20, 2007, 05:43:44 AM
Sammy,

Pin     Volts
3         12v
8          0
L          0
2         26


Looks like the problem is with power to the ECU and shift selector.   Can you provide a point inside the converter box to double check voltage or,,,,, on the inside of the converter, looking at the back of the plug, what color wires may be pins 8 and L?

No work has been done since my last move, wiring or otherwise.

Engine not effected, engine will run more than 10 minutes.

HTH, Please explain diconnect ATEL from power source.  Could this act as a reset perhaps?  Where do I find an ATEC trouble shooting guide?

Thanks guys,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 20, 2007, 05:54:35 AM
Sammy,

Ooophs,,, "what color wires may be pins 8 and L?"  I know this..... and you did say you didn't have drawing of the converter.

Bill



Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on November 20, 2007, 06:00:55 AM
Bill, go on the back of the converter, pins 5 and 6, see if you have an output.
Might have open circuit between converter and ECU.
Check battery cable connections - remove and clean all of them.
I need a diagram of your bus, will try without it , would possibly help.
I'll check back a little later...
You're doing great so far, really.
Sammy  8)


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 20, 2007, 06:05:39 AM
Sammy,

Going to work,,, will have to "play" with bus later.

Spoke to JR, he thought hot wiring 12v in would do the trick. 

Will clean all connectors and battery terminal before trying hot wire trick.

Thanks for the help,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 20, 2007, 12:02:46 PM
Sammy,

Cleaned the battery connection, although they were not bad.

On the Converter;
Pin 5 a Green wire has 4vdc.
Pin 6 a Purple wire has 15vdc.  This purple wire has been worked on.  A new (purple) wire has been run to the push button switches.

I'm a little worried about jumping 12 volts to Pin 8.  It is a black wire and ohms to ground.
"L" does not ohm out to converter pin 6, a red wire.

What do you think?

Bill
Not going anywhere in Gulfport, Ms  :(


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 20, 2007, 12:36:04 PM
Sammy,

Do you have a phone number that is okay to call?

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 20, 2007, 12:44:42 PM
When the connector is connected to the ECU I have 12 volts on Pin L.  Looks like that is an output to something.
Pin 8 is still to ground.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on November 20, 2007, 12:54:29 PM
Bill , Do Not jump Anything.
Still checking the Allison diagrams.

I have 2 diagrams I'm checking - one from 1983 one from 1991 and I have more.
We need a schematic of your bus,to see how the Allison wiring interfaces with the bus wiring.
I am using the 1983 Allison diagram and looking at the 1991 for comparison.
1983 does not show an interface, direct wiring fron converter to ECU.
1991 shows an interface between the two.

Pin 5 of the converter goes to Term 8 of the J2 connector - it's a ground on the 1991 breakout and it just says "battery" on the 1983 one. All newer schematics I have show it as a ground wire too. It checks out as a ground wire so we'll treat it as a ground wire.

Pin 6 of converter goes to Term L of the J2 connector and the shifter in the 1983 diagram - it's a power wire on both diagrams, checks out as a power wire - sounds fine.

Pin 7 of converter goes to term 2 of J2 connector - it's 12 volt power on both diagrams, tests as power, we'll treat it as power.

Pin 4 of converter goes to term 3 of J2 connector, shows as 12v memory wire on both diagrams, tests as 12v wire, sounds good.

Pin 1 of converter is battery ground.

Pin 2 of converter shows as 24 volts into converter.

The 5 terminal strip you mentioned earlier will be on the MCI schematic

That's the best I can do for you so far......still checking..on my day off.....lol..... :)

Pin 3 of converter shows as 24 volts into converter.


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on November 20, 2007, 12:55:56 PM
Bill, I sent you an e-mail with my phone number........... 8)


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 20, 2007, 01:54:38 PM
Sammy,

J2-Pin 2, drops from 26v to 14 v when plugged in.

Guess this means we have all voltages present. 

Will pull ECU and take it to Mobile in the morning to have it checked.

Thanks,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on November 20, 2007, 02:04:46 PM
Bill, happy to help out.
It's a pleasure to work with you.
Please keep us posted.
Regards,
Sammy  8)


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on November 20, 2007, 05:40:31 PM
Is it possible that the converter/ATEC interface includes such things as park brake, and fast idle.
The fast idle could cause a shift problem. 
If any of these items were not functioning correctly, could the end result be a non-shifting trans.  Does the fast idle relay still switch when the fast idle switch is 'on'?  If the relay is full-time 'on' or welded, the trans may not shift?? Sammy?   
When did the fast idle system quit?? 
Another question, do you have a code light and switch in the bay near the ATEC ECM? Does it light up at all when the switch is moved?
I know Bill is not working with a DDEC unit, but my trans "do not shift light" does not illuminate under normal conditions...but it won't shift if the above items are not in the correct position.  With exception of the high idle....which it knocks off automatically.  And the above conditions don't set ATEC trouble codes. 
Could the park brake switch be in the 'on' position?  Fast idle relay issues? 
What I advised Bill to try is to work around the 12V B+ supply.  This is only if the 12V ATEC B+ inputs can be identified postively.    That would give him a baseline for whether his problem is upstream or downstream of the converter and related safety devices. 
A schematic would be really useful to see how the B+ is supplied to the ATEC system.  And is the 12V ignition "on" supplying 12V to the ATEC unit when the master ig switch is in 'run' position?  The 'key switch' power question has likely been ruled out already....?
Reckon we'll have to wait to get more information.  Believe Bill is now on holiday!  8)
JR



   
   


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 20, 2007, 08:27:23 PM
JR,

Bill is not on Holiday Day till tomorrow afternoon.  Then it's off to Tampa, via Jet Plane.

Trying to remember if I used the fast idle switch last time I move the bus.  Just don't remember.

Looking at the Motor Control Wiring schmatic, I see the Fast Idle Switch tied to the Neutral Relay.  Do not see a Fast Idle Relay, are they one in the same?   Off the Neutral Relay pin 2 is a Neutral Switch at the tranny that is N.O.  Even if this was a problem, I don't see it tried to controlling the tranny.   However, it may kill my fast idle.

Going the hour drive to Mobile in the morning early to get a reading on the ECU.  Will post as soon as I know something on it.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on November 21, 2007, 05:25:56 AM
JR,you bring up an excellent point.
Not sure of parameters ATEC is looking for to allow a shift from "N" to "D".
It could be seeing an input for fast idle and inhibiting the shift - I don't know for sure.
Without the schematic for his bus I cannot give a definite answer.I would need to see the fast idle circuit.
Without a ProLink, I cannot check the I/O's of the ECU (input and outputs),to look at what the ECU "sees".
Maybe there are some folks with a similar application that can try to simulate these conditions for all of us and post their results. The "check trans" tell tale light and the "do not shift ' light could be burnt out on his bus, leading us to some kind of shift inhibit problem in ATEC.
Bill's bus,according to the 1983 diagram has no interface - only a voltage converter.
The 1991 bus shows an interface between ATEC and the voltage converter.
I have sent Bill some info and we spoke on the phone already too, comparing notes.
We both feel we have eliminated the basics - power,ground,switched power to ATEC at this time.
Now we wait to hear about the ECU bench test results.


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 21, 2007, 07:56:21 AM
Guys,

Al-Trans is Mobile was unable to bench test the ECU.   They where able to put me in contact with someone in New Orleans that may be able to help a little more.  Meanwhile, the guy in Mobile wants me to check the voltages on the shift selector plug.  Will do that, when I get back to the bus.

Meanwhile, I have a radar problem to take care of at work.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Dreamscape on November 21, 2007, 08:03:19 AM
Hey Bill,

Can't help with your problem just wanted to say Happy Thanksgiving and hope you are able to get it fixed soon.

Paul


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 21, 2007, 08:06:21 AM
Thanks Paul,   I  feel we are getting closer to the fix and with the help of Sammy and JR, I'm leaning ALOT more about this bus.

Happy Thanksgiving to everyone,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on November 21, 2007, 10:06:52 AM
Shift Pad Needed....  Before I can go any further, I need to confirm, or not, that my Allison Shift Pad is working.  If may not be.  I seem to have voltages to the connector, but no lights are working.

So, I need to buy or borrow a shift pad.

Going to put this out on a new thread.

Thanks,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 01, 2007, 09:16:07 AM
Sammy,

Received the loaner shift pad today.   Pluged it in, and nothing, same ole problem.

Thanks for the extra paper work you sent me.

Looking over it now.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on December 01, 2007, 09:58:34 AM
Bill, might need a ProLink now to see what's going on with the ATEC  ECU.
Check out info I sent, might give you some more insight on that setup.
Call me anytime, happy to help as best as I can.
Sammy  8)


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 01, 2007, 10:02:01 AM
Sammy,

There's not a prom that I need to change in the shifter pad is there?

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on December 01, 2007, 10:05:59 AM
No, PROM is in the ECU.
Shift pads are not programmable from my experience.  8)


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on December 01, 2007, 07:29:49 PM
Bill, have you looked to see where the transmission harness interfaces with the coach harness?
Mine has a junction box beneath the drivers seat.  You may be able to trace the trans inputs for fast idle, retarder (this wouldn't cause your problem), park brake power. 
This question is probably redundant, but have you checked for ignition power (12V) at the shift pad?  223B (Red), 225 (Violet), and 235 (White 24V) should be hot when the ign master is on.
210 (Black), and 243(Black), and 230/234 (Black lamp dimmer) should go to ground.
If these are all in order, does the panel lamps work?  Are the grounds patent?
And I've forgotten, but does the 'check trans' light function?  Can you flash out any codes? 
If the ECM  is code free, and the shift pad is correctly powered up, something on the bus such as the fast idle relay may be keeping it from shifting.   The ECMs and shift pads don't cause much trouble.  The wiring may, but the problems are usually at the bus/ATEC junctions.
Don't reckon the PO (or last for hire operator) has the bus wiring diagram?  Something that shows how the ATEC is interfaced with the chassis wiring?  As I said, you may find you can sort the wiring out.  MCI may be able to offer a schematic. 
Good luck!  JR
 



Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 02, 2007, 10:15:13 AM
Sammy, Dallas, JR,,,,,

Thanks for the help as always,  This is what I done this morning.

Sammmy, 

The purple wire, that is patched over something, goes to Pin 4 on the Shifter Pad connector and has 12vdc on it.

Double checked the three fuses, I have voltages on both sides of the fuses.


JR,

On the Shift Pad Connector with power on.

Pins    1,3,5,  have no voltage
Pins    2,4,6,7,8, have 12 vdc
Pin     9, 23vdc
Pins    10, 14 are chassis ground

Dallas,

I've cleaned all the connectors, as discussed.  I have concerns with the data cable to the transmission. 
1.  Do not believe it was locked in place.
2.  The harness side of the connector does not look good. The black plasitc that house the pins, is falling apart.  I cleaned it best I could with the spray and a tooth brush.  Not sure if all pins are making contact.  Perhaps, not all pins need to make contact.  I could use the pin outs if someone has them.  Will try to post a photo of the connector.
Pins    12,13,16 are not used.

Thanks, Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on December 02, 2007, 07:00:23 PM
Bill, if you're sure of your pin-out voltage check, your missing a couple of hot pins.
You said:
Pins    1,3,5,  have no voltage
Pins    2,4,6,7,8, have 12 vdc
Pin     9, 23vdc
Pins    10, 14 are chassis ground


Looks to me as though pin 12 should have 12V, and pin 15 should have 24V?
If the transmission plug is screwed, that's a problem.
Hope a standard HT748 plug is the same.   
Reckon I'd mount a couple 12 post terminal blocks in the engine room and remove the old plug and use the terminal strips to connect the two harnesses together.  Even if that isn't your problem, the trans plug should be repaired.  It will be a problem.
Get someone to cut a trans plug from an ATEC coach...maybe Luke, Nimco, or Sam Caylor has an MC9 with the trans harness intact.  They won't remove it, but they'll cut the trans end off and sell it.  If the plug was your problem, the ATEC would set all sorts of failure codes. 
Does your Check Trans light work?  Grounding "J2" pin "D" will activate whatever memory the ATEC ECM has stored.  You may have a momentary switch in the bay with the ATEC ECM for this purpose.   Or, use a Prolink if you can find one with HT748 data.
The bus engine oil pressure appears to be linked to the transmission.  I'd assume that it wouldn't shift without seeing engine oil pressure.  Nothing has been dinked with regarding the oil pressure senders? 
You have tried all the gear positions...and not just D or Reverse? 
Does your coach have a Robertshaw low oil pressure/hot water/low water shutdown unit? That thing could interlock the transmission. 
JR 
 


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 03, 2007, 04:51:49 PM
Guys,

Had the Allison man here today.

Pin 12 does not apply, this is a 24v system

Pin 15 is a problem, O volts   Does 15 get 24 volts from the ECU.  If so, this could be a problem.

The ProLink, was unable to read the ECU... hummmmm.....

I believe I may be in luck on the Transmission connector.  The schmatic that Sammy sent me, has five pins not used.  I have five empty sockets.


JR,

The Check Transmission light does not lite.  I need to check the bulb.
Oil Pressure is fine, as I seen on my gauges
I tried all the buttons, nothing will shift.
Not sure what a Robertshaw  system is, where do I look?

The Allison man, took the ECU, with him back to New Orleans.  He spoke with someone on the phone, (he's boss I think).  They have a tranny in the shop they believe they can test it on.

Still no clue on the Fast Idle, not working.  Really haven't even looked at that.

Thanks for all the help!

Not going any where in Gulfport, Ms.

Bill



Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on December 03, 2007, 04:58:15 PM
Pin 15 gets power (24 volts) from the interface. Remember : ECU is a 12 volt unit.
Need MCI diagram, to see where Allison harness "interfaces" with the coach.  8)


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 03, 2007, 06:47:37 PM
Sammy,

Thanks for the reminder, you are correct.

Where is the Oil Pressure Switch located?

Where is the Accessory Power Fuse?  Looks like an 8 amp fuse, possible on the same block as a 5 amp.  24vdc runs throught the Accessory Power Fuse, then to the 235 wire.

JR,

Looking on the schmatic,,, I see the 235 and 225 tie together. I don't have the 225, but where is that interface.  It's not under the driver, as I believe your bus mayt be.

Thanks,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on December 03, 2007, 07:36:47 PM

Beats the $#*+ outa me!   Look for any wiring that's encased in split loom.  Most ATEC harnesses are inside black split loom.  The cab harness (if OEM install) comes out beneath the center ramp area. 
Is your shift pad mounted to the RH of the driver?...or LH?  The cab harness exits, more or less, below the shift pad. 
Mine has a "T" off the cab harness that runs across the area above the brake treadle valve.   It interfaces with the kneeler, high idle, and park brake. 
It won't shift when kneeling.  If you shift with high idle, it knocks off the high idle.  But it does shift.   It will also shift with the park brake set...won't go, but it goes into gear.
Look up inside the spare tire area and see if you can locate the cab harness.  If so, see if any wiring exits the harness and routes over to the bus electrical panel. 
My guess is that the interface is in the front electrical panel...next guess would be at the rear junction box.    MCI may have made a harness that runs down to the ATEC too...
Do you see any groups of wiring that separate off near the converter?  TTBOMK, any wiring near the ATEC ECM and converter are solely there for those items.  There's not other wiring in that area.   This is going to take some detective work, because finding a manual with accurate information is not likely.
The bus OEM wiring looks different than than the ATEC wiring.  ATEC has actual colors with numbers imprinted on them.  MCI wiring is generally black, but has numbers stamped on them.   The numbers allow going from end to end and locating the wires.   
White MCI wiring is usually ground (not always), and black is supply. 
What have you decided to do about the trans plug? 
Is your ATEC a retrofit or is it OEM?  Does the cab harness run down thru the tunnel? OR is it routed outside the tunnel below the floor.   There are no splice connections inside the tunnel.  So it you can locate both ends of the harness, you'll be able to follow the additional wiring to power supply...etc.
There's also a small tunnel that runs over the driver's side front axle. The tunnel comes out under the drivers seat.  If retro, your cab harness could be routed thru that area.  Look for the ends of the harness and follow any leads that run into the coach. 
That's the only ideas I have...at this time.
Pin 15 is pulled off the ignition master.  Should have 24V whenever the ign is on.  I believe that's a light?
Good luck!  JR
BTW, have you considered trading your ATEC for an HT740?  Be some work to change out, but damn sure would make troubleshooting simpler in the future.   It would work fine with your MUI engine.   The hardest part would be installing the shift cable...an air shifter would solve that problem.   An ATEC HT748 is a valuable transmission.  Worth more than an HT740.



Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 08, 2007, 10:53:12 AM
Guys,

A have a page of a Wiring Diagram  it is Appendix I Copyright 1991  GMC.  FigureI-1  jSchematic View of the ATEC transmission Control.

Top left of the page is the Selector, this is the connector to the shift pad.   Pin 15 is 24v ign.  The question is,,,  Where is the Vehicle Interface Connector.  Then were does that 24volts go from the 17?

Thanks Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 08, 2007, 12:08:41 PM
Disregard, the last post.  I found it...

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 09, 2007, 08:46:45 AM
JR,

I do not use the Pin 15 voltage. That is a blank.   I've followed your thoughts on the wiring, of course you are correct.

My harness runs in the tunnel.  I'm thinking now it very well be the ECU.  I see to have all my voltages.

If you don't mind, I would like to give you a call.  Need the number.

Thanks,  Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 09, 2007, 02:11:35 PM
Guys,

Here's an update.

The prints I and Sammy have are sort of a guide.  None have been right on.  That has caused me lots of heataches.
I've been looking around the Neutral Relay, thought I might find the problem with the Fast Idle.  Some how, it seem to be connected to the tranny problem.

By removing the wire of the Neutral Relay, screw 2, (located in the Rear Junction Box) and jumping a wire between ground and screw 2, I was able to restore my Fast Idle.... ;D

Then I jump ground to the wire I removed from screw 2...... Wow !  With Sammy loaner Shift Pad, it lit up.... with the Do Not Shift light flashing.....  However, the tranny would not engage with any button.

I changed out Sammy's shift pad for mine....   No "Do Not Shift" light, but then again,,, I've never seen it at anytime. Funny, didn't know I was suppost to have one until I started this mess.....

WOW !   I have first gear, nothing else, but first did engage.  It boils down to a problem around the Neutral Relay area. The print shows a Neutral Switch at the transmission, but so far,  unable to find it, or a wire going to it.

The wire off the relay screw 2 seems to go to the shift pad for the Do Not Shift light.

Input welcome!

Bill




Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on December 09, 2007, 05:25:21 PM
Bill, Wire 231 at pin 9 of the shift pad provides ground to the neutral relay - on Allison diagram.
See what you come up with on your bus.  8)


Title: Re: MCI-9 Transmission won't engage
Post by: Kristinsgrandpa on December 09, 2007, 06:14:11 PM
Bill, there might not be an external neutral safety switch.

My Allison Transmissions  Electronic Controls Service Manual, dated 1 May, 1990,  on page 2-14, section 2-29-b (2) says
two pressure switches are mounted on the valve body and tell the ECU that the transmission is in foreward, reverse, or neutral. 

The manual shows an explode view of the wiring harness and valve body, but no wire no's.  Foldout 22.

That is probably the neutral switch.

HTH,    Ed.


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on December 09, 2007, 08:09:43 PM
Hi Bill,
You've probably answered this before, but if you have a "do not shift" light, you got a code set.   Probably.  If you cannot read  the codes, hook everything back up and I'll tell you how to arrange to flash out the codes. 
Sammy and Ed both have the Allison HT codes.
What have you done about the transmission cannon plug?  Did you say that the plug was suffering from age or deterioration? 
Are you looking for the neutral start relay?  Likely in front drivers electrical panel.  Appears to ground thru the selector.   Shift pad pin 9 grounds wire #7 vehicle (interface) at the neutral relay?
I wouldn't think the trans has a "neutral" solenoid or such.  I is in neutral when no other specific directional modes are being called for. 
The neutral start could also reside in the RJB.  I'll see if I can pull up my old MUI manuals and see where the units were mounted.  There is a separate, exterior to the trans relay that interlocks with several functions.   Door/air step, hi idle, etc.
All of those circles shown Appendix 1, are bus interfacing connections.  Or they may be on a strip, in a cannon plug, or just attached to where ever it was convenient to do so. 
I may have to go to a meeting of the minds AM tomorrow.  We'll be thru before lunch time...EST.
Feel free to call any time after 1000 hours.  If I don't answer, leave a message and I'll call you right back.  May mean  cannot speak at that moment.  But I'll  be aware that I have a missed call, and you number will be kept for ever. 
My number is 704 650 0235.
Sammy generously sent me some of the same ATEC pages you have 
I just have to have a huge magnifying lens to read it.  But I got one!   
I'm about done for tonight.  Really tart all out.  Had to go ride our new light rail  today.  It's nice.  Way to damn many  folk on that thing going both ways.  Alas.  I got where I wanted to go.  Cheap too.  This was Terri's idea.   Terri's a love, and cute too IMHO, so I gotta do what she wants sometimes.  She does like to go...that's why I rarely pull the toad.  She'll wanna go somewhere!    :P
Bill, call me any time after 1000..I'm off tomorrow after mid morning and no inconvenience at all.  Be working on an electric car...screw the Arabs....well, lets don't mess with them too much in bus'n season.   But soon i'll be using a lot less of their fuel on  daily basis. 

JR


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 12, 2007, 03:03:45 PM
Sammy, JR,

I've ordered a used ECM from Nimco, should have it Friday.

I've been looking around the Neutral Relay.

Contact 2 goes to Shift Pad 11.  When the wire is off contact 2, it seems to be getting 14volts from shift pad 11. ???  Of course my schematic shows 2 going to a 2 pin plug on the transmission.

Contact 1 has 7 volts on it.  Traced it back through stud 15 & 12 on the RJB and to stud 4 in the FJB.  All have 7 volts.
Not sure what this means, it may not matter, being as the bus starts.

What do you guys make of this?    ???

Thanks for all the input and the phone calls.   :)

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on December 12, 2007, 07:03:50 PM
I dunno about the neutral switch, but, don't redo anything until the relay wiring is completely understood.  At this point you may add another gremlin!
It appears per Sammy's prints that the wiring isn't correct.  But, it's been working that way.  Considering the potential year model variations, the bus is probably wired as intended.
If the wiring appears to have been modified...that's bad.  If it is intact, there's probably an explanation for the wiring. 
Does anyone offer a schematic of the shift pad?  That would shed light on a mysterious gizmo.
My initial thoughts would be that as long as the bus starts, don't dink with it.  IF the bus starts in gear, or doesn't start...then you'll have to sort that out.
Did you get the various interchangeability issues on the ECM sorted out?
JR



Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 13, 2007, 04:21:41 PM
Without a schematic, I have no way of knowing if it's correct or not.  Could it be that the ECU grounds the relay.   Believe I will leave it along until I get the ECU tomorrow.  I ordered a transmission connecter, just is case.  Plus a dip stick, remember, mine is broke.  I'm concern that I may have too much oil in the transmission. How much, is too much??????

Thanks,  Bill



Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on December 13, 2007, 07:45:31 PM
Too much transmission oil is when it blows it out of the dipstick tube and case vent....and anywhere else it can!   Overfilled would not cause your problem.   If it is overfilled, you can drain some out. Which I recommend.   Otherwise, driving it will cause big aireation of the ATF and problems.  Not permanent problems.
Regarding grounding the relay....it could.  You should be able to shift and verify that the lead goes to ground.  My schematic shows pin 9 for the neutral ground.  Shift the unit and see if 9 goes to ground.
As you say, leave the wiring alone until you understand how it's wired up.  Once it's correctly operating, you can sort out all the oddities presenting.
The correct amount of oil is determined by running the engine and shift thru all the gears and then place in neutral.  Check the oil for correct location on  dipstick.  It must be running.  It will be overfull if shut down.  They are designed to be check hot and with oil all thru the transmission.
JR


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 14, 2007, 03:18:44 PM
 :'( :'( :'( :'( :'( :'( :'(

The ECU came in today,,,, wrong unit.  It has 2 plugs the same as mine, but different type plugs.
Wonder is Nimco will cheerfully take it back and refund my money    ??? ??? ??? ???

This may mean that I don't get to take the bus to Fred's for painting, and won't get to take it to Arcadia.

Sad in Bill Ville


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on December 14, 2007, 06:17:26 PM
Bill, check your e-mail.
Sent you some info on the different ATEC ECU's   8)


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on December 14, 2007, 08:08:26 PM
Bill, did Nimco understand that you have an HT741 and not an HT748?   Take dig pix of the ECM plugs and fire it off to them. 
Unless something's shorted, or 24V got into the 12V system, it's doubtful that the ECM is faulty.  Having a known good replacement would be nice to rule out the ECM. 
Have you contacted Allison to see if they have any ideas on your problem?  It would be remarkable if they even answered the phone. 
JR


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 14, 2007, 08:32:54 PM
Is it really possible to talk to Allison.  I have spoke with three Allison Transmission shops. The first one said to bring the ECU in.  I drove to Mobile, Al one morning, 1 hour, they couldn't read it.  Another came from New Orleans, the ECU wasn't giving up any information.  He started tearing into wiring,,,,, sent him home.  He took the ECU, thought they would read it at the shop.  Of course they couldn't.  I went to New Orlean 88 miles, to reclaim it.

Nemco, knew I had a 741.  They didn't have an ECU 1226010.  They thought the 1228283 may work.  I agreed, not knowing that the plugs would be different.

I see the one I need on the internet for $900.00    See another company that claims they can rebuild them.

Would love to have a replacement to try.  Know of one ?????  Only need it for 10 minutes..... ;D

Tomorrow I plan to ohm out the tranny connector, see if I can find a problem in that area.

All suggestions are welcome.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT 5573 on December 15, 2007, 03:24:17 PM
Bill, I experienced a variety of problems with my ATEC.

 My shop guy told me to clear the codes and everything would reset and be fine. I cleared the codes and everything reset and was fine.

 My ATEC wiring has periods of glitches. Two weeks ago I swung across the highway to back into a yard and got a glitch. Across the road and won't shift!

I cleared the ATEC codes real fast, pushed the R and my full transmission was restored.  I backed off the highway before people in cars could even have known I had a shut down hickup.

I experienced similar problems with my DDEC, but after turning off few extra parameter DDEC settings, I have also made peace with and developed some confidence in my ability to keep one on the road 24/7.



Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 15, 2007, 03:34:01 PM
How do I clear the codes?

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT 5573 on December 15, 2007, 05:21:31 PM
Bill, I have a Eagle

 It has a toggle switch on the dash, up to read engine codes, down to read transmission codes.

To clear the ATEC codes, (engine running), I hold the switch down and push R and then D three or four times to cycle the computer and I have a new reset tranny ready to go until the next time.

If you need cheap parts, call, 218.262.4553 ask for Randy, He's got it all.


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 15, 2007, 06:50:07 PM
My MCI does not have that option.

Ted Keating (TKT) is loaning me an ECU 1226010, like mine, for me to try.  He's overnighting it Monday, I should have it Tuesday.

Wish me luck.  Really getting tired of this problem.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on December 16, 2007, 10:35:33 AM
That will help resolve the problem one way or another...rule out or prove the ECU.  Are we placing bets?  ;)
I hope that solves your problem...but, if it does, that opens another can of worms.
Hope the weather isn't killing you! 
Post the outcome!
JR


Title: Re: MCI-9 Transmission won't engage
Post by: Stan on December 16, 2007, 12:06:15 PM
There are pros and cons to troubleshooting with a spare unit. The pros are obvious bur the cons are that if the original unit was damaged by an external fault, the spare unit will also get damaged. Probably the most likely causes of this scenario would be getting 24 volts into a 12 volt device or a short to ground on an output.


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 16, 2007, 06:22:47 PM
Being that I have checked and doubled check the grounds and voltages, I believe it is safe to hookup the spare.
It is well known that electronic devices fail mostly on shut down or start up.

One,,,,The problem developed either, when it was shut down last time I moved it, or during startup. 

Two,,,,We know there is a ground missing that the ECU sends through the shifter pad, for the FAST Idle.  If I replace this ground with a jumper, the fast idle works fine.

I'm putting my money on the ECU.  If I'm correct, I roll out of Gulfport, Ms Wednesday.  If wrong, I fly to Tampa.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on December 18, 2007, 01:20:39 PM
 :( :( :( :( :( :( :(

Installed the loaner ECU, after changing the PROM,  no fast idle, no lights on shifter pad, and NO engaging transmission.  Really now believe it has to be in the ground circuit with the fast idle.   BUT HEY,,,,,,,,,,,,

I'm driving  (instead of flying) to TAMPA,via car, for Christmas, then will four wheel it to Arcaida for the day.   With luck I can find a MCI-9 that I can look over.

Everyone thank you for the help.   :)      I will take this back up, NEXT YEAR.

Bill   ;D


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 03, 2008, 07:00:58 PM
Okay, here's an update.

It's cold here.... :o in Gulfport, Ms.

Dallas is spenting a few days here, to help me trace out wiring.  We found a ground wire from the shift pad that didn't seem to be grounded.  That was part of the problem with the ground to the Neutral Relay.

What I have now, is a loaner shift pad from Tom at Heartland Coach in Arcadia.  It's lights up, and I have still have "Do Not Shift".  We now think that something is telling the ECU that there is a problem.

With a loaner ECU from Ted Keating, the ECU is once again flashing codes.  Something my ECU wouldn't do.  We are getting a 21 code, which is the Throttle Sensor.

Sammy has been a HUGE help.  I've lost count how many phone calls have been made and how many pages of information Sammy has scanned and e-mail to me.  The last set along is 21 pages. 

With our new data on the Throttle Sensor Trouble shooting, supplied by Sammy,,,,,, Dallas and I, tomorrow will be looking for a Throttle Sensor problem as soon as we double check the ECU is not carrying over codes from it's last home.

Wow,,,, have I learned a lot.  Not sure how many buses I checked in Arcadia.  Sure people were wondering why I was asking everyone "What Transmission Do You Have?"  Almost everyone has a Allison 740.  I am the only one with the 741.   ??? >:(      Just my luck.  (note to self, next bus, too have 740 tranny).

Anyway,,,,,That's what happening.   

Bill



Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 03, 2008, 08:05:34 PM
Hi Bill, it's cold up here too!  Real cold!   :o
Is your TPS mounted on the engine?  Your code is a good start for resolving the problem.
TPS might be the whole issue. 
Once you get the transmissin working correctly, it'll probably never give any more trouble.
ATEC transmissions shift smoother than HT740s...still, as you have found, diagnosing wiring faults can be a nightmare. 
Sammy, Bill's transmission issue have scared the poop out of me.  Do you have a part number for an Allison HT748R diagnostic manual?   I have a wiring diagram, but nothing with the codes and such.  I  have a DDEC dx manual.  It's worth its weight in gold!
I believe Allison still offers the HT ATEC manuals.  However, their website only lists one "Electronic" diagnostic manual...that sounds like it would have to cover a lot of territory?
Dallas, you did move a right good bit!?  Where ya'll headed?  Tell Cat HAPPY BIRTHDAY!  ;D
Reckon this is her 29th?   
Bill, Dallas and Cat, and Sammy, stop by if ya'll ever get up this way.   JR

 


Title: Re: MCI-9 Transmission won't engage
Post by: NJT 5573 on January 03, 2008, 09:14:49 PM
Darn, 21 code huh. Throttle sensor huh! Well if I were a fancy "computer" transmission, there is no way I would let my transmission engage until that code was cleared. How did you read that code anyway? When my atec codes out it won't shift either. I think if you go into read code mode, (how ever you did it), and then simutaniously push r/n/r/n/r/n on the pad, ( new pad $200, don't spill pop on it), that old 21 code will go away and off you will go.

You better find out how to clear these codes. Some of the electronics pulse thousands of times a minute and 21 codes are not abnormal. Changing the ECM should get you one that has no codes but the real problem here is that you don't know or have not cleared the codes and you will go broke buying parts you don't need.

 Seasonal changes cause my atec to run false codes at random and this transmission is determined to protect its self until all codes are cleared.

 If you clear the codes and go a few miles and they reset repeatedly then I would replace the throttle sensor if its always a 21 code. If all else fails, call Randy, he's an expert and has every part ever made for DDEC/ATEC on his shelf, cheap, its all he does.

I have an atec manual, but I don't think you need one.

My atec is very sensitive to any input by me. If I try to select gears it will often code out. You have to just put this trans in D and let it do its thing.

You have been down quite a while and still have a code, you must start by clearing the code.

Codes don't really mean anything is wrong in my experience. The guys in the shop call these codes hickups. Clear the code, check the fluid and keep on trucking.


Title: Re: MCI-9 Transmission won't engage
Post by: makemineatwostroke on January 04, 2008, 12:18:40 PM
isn't the 21 code a high voltage problem at the throttle sensor


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on January 04, 2008, 12:50:07 PM
It's an ATEC code, not WTEC.
There is no sub code like WTEC has, only complains that TPS signal is out of range.
Sammy  8)


Title: Re: MCI-9 Transmission won't engage
Post by: makemineatwostroke on January 04, 2008, 01:22:17 PM
Sammy,sorry i should remember that its a 741 Bill has been working on for 2 mos and I my condolence goes out to him


Title: Re: MCI-9 Transmission won't engage
Post by: Sammy on January 04, 2008, 01:36:13 PM
 :), lol
Yes, it has been a struggle.
He finally has a hard code (with the loaner ECU), now almost finished troubleshooting it.
Regards,
Sammy


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 04, 2008, 03:18:38 PM
Guys,

I've cleared the codes.  The ECU kept flashing the 21 code

Dallas and I ran through all the Throttle Position Sensor Trouble Shooting Guide. The item that looks to be a problem is the TPS (Throttle Position Sensor) itself.

Being as it was almost 4pm CT, I started calling parts places out west.  I had hope to get one out to me,  TODAY...

John Allen of Bus Service, Inc, in Kansas, had a TPS ($155.00) on the shelf and was trying to get it out today.  If not, he will be able to ship it tomorrow.

IF the new TPS corrects the problem, I will install my ECU and see if it works.

That's all the news that is the news from Gulfport, MS.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 10, 2008, 06:22:23 PM
Update,,,,

Have the new TPS (Throttle Position Sensor).  A little trouble removing the old one, due to rusted bolts in the block that holds the TPS cable.  Have it soaking, hope to get back to it tomorrow, weather permitting.  If not, will be Saturday.

Hope this fixes the problem, will have to roll out of Gulfport soon.  I have accepted a new job with Raytheon in St. Petersburg, that I start Feb 4th.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 10, 2008, 06:39:59 PM
PB Blaster is good stuff.  So's a heat wrench if you can use it without burning the coach.   Even heating the bolt heads and letting them cool will often cause them to loosen.  Definitely help wick up chemicals. 
Is Dallas and Cat still down there? 
Waiting for outcome!   JR    8)


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 10, 2008, 06:43:52 PM
Thanks JR,

Dallas and Cat, moved East to Florida, I think.  Dallas help me, go through the wiring.  Would have taken me forever, by myself.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Dallas on January 11, 2008, 05:33:40 AM
Bill,

and JR,

Cat and I are still in Lillian, Alabama working on a 1950 Flxible that got a kind of a little hole in it's nose. We'll know more today if it's gonna be possible to make a runner out of it or if it will end up being an Organ donor for other Flxies.

Bill, If you really need help, we'll probably be here about another few days to a week working on this critter. Give us a call, you have our numbers.

Dallas


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 11, 2008, 01:36:18 PM
Replace the TPS today, no glory.  ECU is still flashing a 21 code.  Starts one to think if the borrowed ECU is 100%.

At this point I'm clueless.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 11, 2008, 07:49:55 PM
Is the wiring between the TPS and ECM intact, not to ground (one lead probably should be when plugged up to the ECM?) and power on one lead?   Sorta talking out my a$$ on this since I don't know what your TPS looks like. 
Will the codes clear?  Do they reset, or are the codes just "there" whenever the ign master is turned on?  Interesting that your ECM doesn't set the same code if the fault is in the TPS..or TPS wiring.   
Does the TPS resistance check correctly at the ECM plug?   Sammy could (probably has already) give you the resistance range for the TPS.  Are you sure you have the correct TPS?
Looks like J1 pin 6 should go to ground (thru the ECM), pin 4 is TPS output (should have variable voltage with TPS movement), and pin 24 is 5V power to TPS.
You've probably already checked the wiring, but, J1/6 should have continuity out to TPS pin "C", J1/4 should go to TPS "B", and J1/24 should read to TPS "A".  None should go to ground when unplugged. 
Looks like a temp sender in the transmission is grounded thru the TPS/ECM terminal J1/6.   Is there continuity thru the temp sensor?  Not sure whether that would set a code thru the TPS circuit, but it is grounded thru the TPS ECM ground.
Need someone with an ATEC to disable the TPS and see if the transmission will still shift.  I think it would.  Probably shift into second gear and reverse.   There's probably a transmission limp mode.  If that's the situation, the TPS could be ruled out.   
 
Do you have a schematic of touch pad?  Be interesting to check the function of the touch pad at the J2 plug. 
Unless you find some old-timer that has a ton of experience with HT741/48, sorting out the problem may be beyond most technicians.  Even a simple wiring problem can be a nightmare for most mechanics.     
Still a possibility that the transmission is at fault.  Not likely really.  I keeping my money on the wiring....or exterior components. 
Reckon there's any way to test the cannon plug at the transmission for correct input?  Such as power to forward or reverse?  The plug would have to be checked while attached to the transmission.  Otherwise it'd probably set a list of codes.    Is there a test unit that the trans cannon plug plugs into for diagnostics?   That would be a useful item.   
What about a ProLink?  Did you ever get that unit to read at the DDL plug? If not, back to the wiring.  The DDL is simple to get attached to the ECM.  If necessary, run the wiring exterior to the DDL so that the transmission can be read.  The new ECM may have stored data. 
Reckon you can get Sammy down there?  Be worth a considerable gratuity to have his experience for a day or two?? 
What's happened to you is my worst nightmare.  An ATEC problem that cannot be readily diagnosed.  Bummer!
Hope something works out soon!  JR 
 


Title: Re: MCI-9 Transmission won't engage
Post by: NJT 5573 on January 11, 2008, 10:41:08 PM
Bill, don't know if this will help but.... In my learning experience with ATEC a few years ago, I discussed using my ATEC transmission with a mechanical engine with my local shop foreman at DD. He told me I would only need to have one thing, a throttle position sensor, for my ATEC transmission to function with the mechanical Cat.

In my experience the shift pad got wet and set a shut down/ do not shift code. I think a shift pad could contain the TPS brain. I took mine apart and it has enough circuits to do a shuttle launch. I did the $200 exchange deal and solved the problem, but I knew it had gotten wet. Does your roof ever leak? You could next day air any of your parts in question to ----- and get them back in next day air.

I'm not convinced that you have cleared the code. If you have it must be a solid failure to immediately reset. Have you had the shift pad out to be sure the wires are tight on the back?

The manual tells step by step testing to determine and repair a hard set 21 code. If you don't have this info I will dig my manual out of the cargo bay in the morning.


Title: Re: MCI-9 Transmission won't engage
Post by: niles500 on January 11, 2008, 11:53:59 PM
Niles500
Sr. Member

 Online

Posts: 379


ROSIE


     Re: MCI-9 Transmission won't engage
Reply #41 on: November 19, 2007, 11:53:18 PM Quote Modify 

--------------------------------------------------------------------------------
Before I get flamed - just as a pleasant reminder - disconnect the ATEC from its power source for a 10 minute period - when reconnected shift to neutral - if you can't get a neutral indication see ATEC trouble shooting  guide - HTH


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 12, 2008, 06:29:39 AM
Thanks for the input guys,

Here is where we are.

1.  Shift pad is a loaner from Heartland.  Believe it is good.  The only difference between mine and it, as Heartlands has a "Do NOT Shift Light".  Mine does not. (mine doesn't have the bulb).  All the power and wires are good to the shift pad.  Dallas and I did find one ground wire that didn't seem to be intact. That has been corrected.

2.  My ECU doesn't flash codes.  The loaner from Ted Keating's loaner, with my PROM, flashes a 21 code.  With the trouble shooting guide that Sammy e-mailed me, Dallas and I went through all the items.  They were all good.  The only concern was the test of the TPS itself.  I replaced the TPS, the ECU is still flashing 21, and will not reset.  NOTE:  We tested the TPS with a digital meter, I now believe it didn't give us correct reading.  I now believe we do not have a code 22 problem.   I'm not sure that the code has reset.  I've been through the steps more than once.  Will try once more, will unplug the ECU for ten minutes, plug it back in,, start the engine, then shift N to R.

3. While crawling in the engine compartment yesterday. I found my Speed Sensor has a problem.  It is not screwed on, the threads are stripped.  The Allison Transmission Troubleshooting Manual states that the transmissionwill not shift if the Speed Sensor is faulty.  Of course the huge question is why isn't the ECU flashing code 22. 

I need a littel education on the Speed Sensor.  Sammy says it a Signal Generator type.  Going to pull it now....

4.  I would gladly overnight and back a couple parts, if I knew someone that could try them in there bus.

5.  Do not have a schematic for the shift pad.  Would love one.

6.  Sammy and I have talked about getting a Prolink here again.  Don't believe that it will do any good, 1, being a have a code, and 2, I can't clear that code.

7.  Dip Stick..... remember, the end of my dipstick broke off and laying in the bottom of the pan.  Question,,, is it laying in the bottom of the pan, or is it, laying across the Low Oil Level sensor.  Someone needs to give me a little input on this.

Thanks guys, keep the input coming.   This bus has got to roll.  I start a new job in Florida Feb 4.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: belfert on January 12, 2008, 08:01:08 AM
There is a company up in northern Minnesota that folks always recommend for rebuilt shift pads and other electronic parts.  They would probably have schematics.  Good luck.


Title: Re: MCI-9 Transmission won't engage
Post by: makemineatwostroke on January 12, 2008, 08:32:15 AM
Bill,try calling S & J Chevrolet in Cerritos CA at 888-935-3335 talk to Adrian this outfit has some good techs and may can help


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 12, 2008, 08:47:51 AM
What is name of the company in Northern Minnesota?

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: belfert on January 12, 2008, 08:49:42 AM
What is name of the company in Northern Minnesota?

Ask Bryce (Busted Knuckle).  I don't have his phone number handy, but Dallas would have it.


Title: Re: MCI-9 Transmission won't engage
Post by: NJT 5573 on January 12, 2008, 06:45:42 PM
I have already given Randys phone # in MN in an above post. These people are sharp. They have every part for DDEC and ATEC including every harness and connection ever made. They service the DD dealers nationwide but sell to the little guy at huge discount.

These people also know everything there is to know about these units and how to keep them running. (DAMN)! Gen Die Electric (Randy) helped me by checking my parts and returning them to me at his cost. (He paid the next day air out of his own pocket). I have never been treated so well! They were good, and I still had the same problem you have. I called, he asked me "did you clear the codes"? I said "gee how do you do that"? He told me and off I went. He also sent me a FREE ATEC manual just to help me out. We know your codes don't clear the same way as mine, so what is the trick?

Sometimes you can lead a horse to water but you can't get him to take a drink! I need to get the book because I think there is something about the TPS having to relearn its job and a certain way to do it. I don't go anywhere without GDE's phone # because I know he will send me next day parts anywhere and talk me through any problem I have.

I don't know if he gave me special attention because I own a trucking company and truck repair business or not, but I think they will treat you well.


Title: Re: MCI-9 Transmission won't engage
Post by: NJT 5573 on January 12, 2008, 07:39:51 PM
Ok Bill, here's what the book says about the 21 code. "After clearing, a 21 code may require as many as 5 cycles of "keystarting" (turn on power to ATEC and turn off power) to reset the self calibration feature of the throttle sensor.

To clear all diagnostic codes, the test switch must first be in the on position; then select reverse and go back to neutral. If a code does not clear, the problem is still present and must be corrected before the code will clear.

A 21 code,
a. will be caused by a throttle sensor failure
b. will be caused by a throttle sensor overstroked (either direction) entering fail zone.
c. could be caused by an open or short in chassis harness.

Check TS linkage, verify input cable to TS moves when throttle pedal is depressed. Close attention should be given to engine fuel lever, loose connections, and binding of cable.

The rest is test and repair info and is extensive, (20 pages) and mainly is trouble shooting and repair of chassis harness damage.

If you need the book I will next day it to you, let me know.


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 12, 2008, 07:56:59 PM
JR,

Just scanned eight pages of post.  I don't see where you posted Randy's number.  May I please have it again.

Currently my Speed Sensor is bad, I will order a new one Monday.

Interested in trying to clear the 21 code some more.  You said up to five times.  First time I have heard about the 5 cycles.

Thanks,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 12, 2008, 08:03:43 PM
Sorry Bill, but that wasn't me...that's Larry.  The OTHER NJT guy.   ;)
I'm waiting to get it too.  I'd like to check on some ATEC manuals.   The 'trans man' sounds like someone we should know.

JR


Title: Re: MCI-9 Transmission won't engage
Post by: NJT 5573 on January 12, 2008, 09:40:46 PM
The # I have is 218.262.4553, sorry, I thought I had posted it, maybe mod deleted it.

I found the # at the bottom of page 6, think I was tired and didn't do a good job explaining myself. Hope he/they can help.
My understanding is, first clear the code then reset the unit, if I read it right. Seems like you would have to do it the other way around though. Fun Fun Fun.

Key off probably means master power control off, but could be just dash power off, I don't know but I wrote the instructions word for word from the manual. Try both!


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 13, 2008, 09:13:04 AM

They have a website too.  http://gendieselect.com/
Located in Hibbing. 
JR



Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 13, 2008, 03:49:27 PM
Went through the Code 22 (Speed Sensor) Trouble shooting and once again through Code 21 (TPS) Trouble shooting guide.  Found no problems with either.   Tried resetting the ECU, with the 5 cycle approach.  Did it by switch the dash switch on and off, and the main power on and off.  Both with the code switch in the on positions, switching between R & N.

Dallas and I went through Code 21 trouble shooting chart, thought maybe we had a bad TPS.  I've replace that, and I have gone through the Code 21 trouble shooting chart again.  At this point, I do not believe it is Code 21 TPS that is a problem.  However, as stated, the ECU will not clear the fault.  Starting to believe the loaner ECU may have a code 21 hangup.

Plan to call Randy, and Baker Transit Parts, plus a couple others, to pick their brains.

Any thoughts,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 13, 2008, 04:04:44 PM
NJT5573,

Which ATEC book do you have?  Sammy and I have been working from his 1991 for the Splash-Proof connectors.  This seems to be the closest to my set up.

Thanks,

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: niles500 on January 13, 2008, 04:43:16 PM
http://www.tpub.com/content/constructiontractors/TM-9-2320-364-20-1/0726280288.htm

http://www.tpub.com/content/constructiontractors/TM-9-2320-364-20-1/0726280290.htm

http://www.tpub.com/content/constructiontractors/TM-9-2320-364-20-1/0726280292.htm

http://www.tpub.com/content/constructiontractors/TM-9-2320-364-20-1/0726280294.htm

http://www.tpub.com/content/constructiontractors/TM-9-2320-364-20-1/0726280296.htm

http://www.tpub.com/content/constructiontractors/TM-9-2320-364-20-1/0726280298.htm

http://www.tpub.com/content/constructiontractors/TM-9-2320-364-20-1/0726280180.htm

http://www.tpub.com/content/constructiontractors/TM-9-2320-364-20-1/0726280181.htm

I have the info on when you can't clear codes, but it may only be fore DDEC III/IV - HTH


Title: Re: MCI-9 Transmission won't engage
Post by: NJT 5573 on January 13, 2008, 05:39:57 PM
Bill, I have the Splashproof Standard ATEC automatic Model V731 munual, Copywright 1987.

Randy gave it to me and told me there was very little difference between the V731 and my HTB748R.


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 13, 2008, 06:09:33 PM
Bill, do you know what the loaner ATEC ECM you're using came out of?  Was it a DDEC engine?
If so, the ECM may be looking for com data from the DDEC unit.   
The DDEC ECM feeds the TPS signal thru the link.   Non DDEC TPS units are wired thru a different set of leads.     
You've got an unusual animal with the 'stand-alone' ATEC.   
The "loaner" ATEC ECM may not be correct for your application (MUI).   It would seem reasonable that the ECM for DDEC and MUI may be programmed diferently. 
Have you tried your ATEC ECM since it was removed? 
You may have to reinforce the fact that you have an MUI engine when discussing your problem with professionals.
JR



Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 13, 2008, 06:24:38 PM
JR,

If I change the PROM from my ECU to the loaner, would it matter what it came out of?    When I change ECU, I change PROM.  However, with either ECU or either PROM, the transmission acts the same.   Will not shift, except in "1".

With my ECU the code light remains RED..... The loaner ECU flashes a code 21.  Of course we are starting to believe that's not correct either.

Really need a bus that I could plug my ECU into, see if it's bad or not.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT 5573 on January 13, 2008, 06:41:14 PM
Bill, why not send it to Randy? I bet its cheap to have it tested.


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 13, 2008, 07:02:03 PM
I'll call him first thing in the morning.  If he can test it, I will overnight it to him.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 13, 2008, 07:16:53 PM
Assuming the EPROM is ok, I suppose that should set the programming to your specs.  
I believe Larry's got the right idea.  Let someone rule out the ECM...if that's possible.  Red lable UPS for fast service.  
I was looking at Niles' "TPubs" thing, but that all relates to DDEC II and up.  Not sure if there's any difference (electronically speaking) in any of the HT700 (or V731) ATEC series.
Looking through the 'net found a company with an elaborate Allison website...Valley Diesel Power or some such.  Google Allison and they'll come up.   They offer Allison training schools.   Most of there offerings are related to WTEC.  Still, they probably have HT familiar employees too.  
Don't know about your financial situation, but maybe you could fly Randy down to your bus?
I still cannot imagine that the broken dipstick is causing a problem.  If it was, you'd get a code on the circuit failure.  There's a temp sensor in the transmission that won't let it shift until the temp is above 20*.  Something in that circuit could (big "IF" could) cause non-shift if the wiring failed.  The temp sensor shares ground with TPS.   Unsure what a temp sensor failure would code too.  Don't have a dx manual.  I will have soon.
Pull the air cleaner, remove the dipstick housing, and use a extension magnet to fish out the broken dipstick.  You may get it out that way.  Dropping the pan and losing a lot of ATF is the only other way to get it out.  
Good luck, JR


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 13, 2008, 07:30:09 PM
JR,

The Temperature Sensor is code 33.  Sammy just e-mailed me the trouble shooting guide for that.  What we are doing is eliminating all the codes that will stop the tranny.  There are about 12 of them.


        Item                                    Status
Extremely low oil level                      Done

Oil Temp too low

Voltage to ECU too low                    Checked and rechecked

Throttle Sensor (code 21)                Check, checked and replaced

Range Selector                               We feel this is working

Disconnected or dirty Connectors       All have been checked and cleaned

Faulty wiring harnesses                    Could be,,, but we have checked and checked this

Speed sensor                                 Checked

Faulty H Solenoid

Faulty F,D or J Solenoid

Hydraulic problems

Faulty ECU

As you can see, Sammy and I are attacking them one at a time.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 14, 2008, 09:58:15 AM
Spoke with Randy,  my ECU is being overnighted to him.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 14, 2008, 04:35:02 PM

The outcome of Randy's evaluation is going to be interesting.   
Did Randy offer any suggestions?
JR





Title: Re: MCI-9 Transmission won't engage
Post by: compedgemarine on January 14, 2008, 04:46:56 PM
WOW. sorry for all your troubles but sure makes me glad I have an old DD before all the electronics. If mine doesnt work it is usually me.


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 14, 2008, 05:08:53 PM
JR,

Not really,,, he was pointing a little towards the three switches (R,N,D) in the tranny  :(

But wanted to look at the ECU.  Which by the way is $150.00.  ???  Then a "little" ??? >:( more, if there is a problem.  Hope to have it back by Friday. (I can wish anyway)

Meanwhile, Sammy is spending hours scanning and e-mailing me most of the manual.  Thanks Sammy, your my hero.

Now who was it that had a manual they didn't mind loaning me.  If it is still available, I will take you up on the offer. 

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 14, 2008, 08:26:19 PM
Sammy can verify, but I believe most of the electronics inside the trans can be replaced once the pan is off. 
All in, or on the valve body.
I've been looking at ATEC manuals...can you imagine that!   Coachinfo has a manual for the HT748...but not sure it has the diagnostics.  Have to call or email to see exactly what they are offering. 
After watching what you're going thru, I'm definitly going to get a diagnostic manual for my 748.  I think it's the same as yours...but it's connected to a DDEC engine. 
It would be nice to find out the ECM is the problem, and it sounds like it may be.  Both seem to have issues.
Could be the EEPROM.  A DDEC EEPROM isn't expensive at all.  I bought one of the bastard DDEC 1 EEPROMs for about $125 bucks.  Made a huge difference in highway performance...enable my cruise control which is really nice on flat roads.
It would be cool to have a working relationship with an ATEC repair facility too.   At least an electronic repair facility.
Where does Sammy hang his hat?   He would be invaluable on site.   
Oh well, reckon we'll have to wait for word from Randy.  Suppose he'll let you know what he finds once he runs diagnostics.
Do they have a test-bench for ATEC/DDEC ECMS?   Or some sort of emulator?
Good luck, JR



Title: Re: MCI-9 Transmission won't engage
Post by: NJT 5573 on January 14, 2008, 08:58:23 PM
Bill, at this point why don't you just tell Randy that you know he gave a free manual to the last conversion bus guy he helped out and you think he should give you one too!

I think General D&E and Sammy will get you sorted out at this point, manual or no manual. I don't trust you with mine anymore!

I wonder if Randy can pull all your history codes from the parts you sent him?



Title: Re: MCI-9 Transmission won't engage
Post by: Kristinsgrandpa on January 14, 2008, 09:58:59 PM
Gents, 

I bought a manual from Allison, the cover says "Service Manual HT, HTB 700 Electronic Controls Series Transmissions".  SM2004EN    Dated 1 May, 1990

It covers the HT, HTB 741
                   HT, HTB 748
                   HT, HTB 755 CR
                   HT, HTB 755 DR
It only shows wire harnesses and solenoids, it shows the shift pad and wire harness and that is all.

It appears to be quite comprehensive in the hydraulics and mechanical sections but is lacking in the electrical section for troubleshooting.  No schematics at all.

I does show the temperature sensor and all the solenoids in the valve body. They appear to be accesible with the pan removed.

I'll be looking for a trouble shooting guide, something with schematics etc.

I do have a DDEC II Diagnostic Troubleshooting Guide, appears to be quite comprehensive.  Dated May 1988. It has some updated info sheets in the front.

Ed.


Title: Re: MCI-9 Transmission won't engage
Post by: JohnEd on January 14, 2008, 10:25:41 PM
Ed,

My heart bleeds for you....really.  I am a trouble shooter from the early 60 on up till present.  Radar and other large systems.  The old style rule in trouble shooting is to use the "split half" method.  Today they trouble shoot by replacing "modules".  They get to having so much faith with this method because the same problem is almost always in "that module".  My generation did split half and then hand over hand to the failed component.  I think you need "old school" but I am not bus savvy.

You have a number of major components in the system.  I would go to the component/module that is at the closest point to the trans.  Guess that would be the Trans Control Module.  It only has so many inputs that control it.  Dummy out each....ground what should be a ground in normal ops....open what should be open....a resistor for what is normal....+12 for what that is.  When you are done it will work or not and you can concentrate on what is before of after the TCU.  It it works, start reconnecting circuits till you get the failure back.  You have to get as close to the ecu circuit as possible and inside the can and on the tcu side of the connector.

Another problem I see is with the circuit conditions being specified for a connected TCU and you disconnect the plug to get at the wire to measure.  There are often loops that require that the connector be connected for you to see that ground or voltage.   Unless it is a spec for the connector being off.  Goes both ways. 

You are in a bad way with this and you need to rule out some of this stuff.  We trouble shoot to eliminate things as possible failures.  I probably should not even open my mouth because you have gotten very smart people involved in your problem and I certainly can't hold a candle to their expertise.  Sincerely!  I have been following your adventure like a soap opera and the whole thing upsets me.  So many good minds, so many years of experience, so many hours of labour and still NO JOY IN THE COCKPITT.  We always win in the end, never forget that.

For morale support,

John


Title: Re: MCI-9 Transmission won't engage
Post by: Dallas on January 15, 2008, 04:27:42 AM
Bill,

I'm kind of with John Ed here on this, although I think at this point we may want to look at the transmission itself and start the split half there. I never did hear any of the transmission solenoids click, except when we had first gear.

Now, if we have first gear, does that mean we have 2,3 and 4 also? Is it possible the reverse solenoid is FUBAR and that is giving the donot shift light?

As much time and effort as you have into this transmission, I still lean toward a strictly electrical problem.

If you need help, holler, we're still close by and have extra hydraulic jacks!

Dallas


Title: Re: MCI-9 Transmission won't engage
Post by: JackConrad on January 15, 2008, 05:21:37 AM
Bill,
   I don't know if this is relative or not, but on our F350 Ford diesel dually pickup, we fought erratic shifting for several years in a Ford rebuilt transmission we had installed (OD light would flash on shift lever=fault). Had it back to the Ford dealer many times. They kept telling us it had to be something else because the computer said the trans was working properly. We then took the truck a privately operated transmission shop. He had the truck for about 1 1/2 weeks and he did a lot a head scratching and talking to several tech service companies. Final diagnosis was that everything was working electrically, BUT the 4th gear solenoid was not working MECHANICALLY!   I wanted to take the bad solenoid back to Ford and throw it at their "transmission service tech" but Paula said NO, just call them and tell them.  Jack


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 15, 2008, 11:38:10 AM
I've just spoke with Randy.  He say's my ECU is bad.  The chip (s) in the TPS circurt, have a problem.  The cost of repair, that and any other problem is $800.00   I said fix it.  He will try and have it out of his shop by Thursday.  He will waive the $150.00 to check it out.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 15, 2008, 06:10:38 PM
Next question (which you may have already axed) is what could cause a TPS related failure in the ECM?  One thing that comes to mind is getting 12V...or 24V on the sense circuit due to wiring problems...or during dx. 
Does Randy believe this sort of failure to be spontaneous?
Stuff happens.
Hope that sucker has about 5 years warranty! 
Glad to hear that something's proven to have failed.  Is that your ECM, or the 'other' ECM that was sent to Hibbing?
Spending $800 bucks should allow you to pick Randy's brain for a bit. 
Waiting again!   JR



Title: Re: MCI-9 Transmission won't engage
Post by: Dreamscape on January 15, 2008, 06:13:11 PM
Gosh Bill,

I sure hope you found the problem. Sounds like this Randy fellow might know a thing or two. Good Luck and always be safe.

Paul


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 16, 2008, 09:12:03 AM
Randy called,,,,,,  My ECU is  fixed.  It was the TPI input chip.  Should have it back Friday ;D.  Before installing I'm going to go through the CODE 33 (Shift Pad) Fault Trouble shooting guide.  Just to make sure I don't have a wire or something I missed.  Randy said the chip was shorted to ground.  Which caused my ECU to not flash a code.

I'm praying to the bus gods that this corrects the problem, and I can roll on my merry merry way.

Bill


Title: Re: MCI-9 Transmission won't engage
Post by: buddydawg on January 16, 2008, 09:15:30 AM
Great! Look like things are finally looking up.  I hope whatever caused the problem was just a one time fluke of sorts.  I would hate for it to short out again.  (I know you would)


Title: Re: MCI-9 Transmission won't engage
Post by: JohnEd on January 16, 2008, 11:09:03 AM
Bill,

The absolute worst problems to find are the ones where "two" malfunctions occur simultaneously.  When I bought pubs for the Navy I verified every step of any troubleshooting guide/procedure.  Those books were encyclopedic.  I was once told that to include a guide that addressed the symptoms for dual failures would cost in the multi trillions of dollars.  Now, the bright side of this is that if you still have a failure....it will be far,far more simple to find.  I think this is the fix you were looking for based on my HUNCH, though.  Love it when a plan comes together for a guy that richly deserves it.  Good Luck.

John


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 16, 2008, 02:07:14 PM
Good that the ECM is diagnosed and repaired...but first, the obvious.   Verify that the none of theTPS circuit leads (power, sense, and ground) have continuity to the chassis.    I suppose that would include the trans temp sensor too.
TPS may have been your problem after all.
Checking all the wires in an ATEC system is a mind boggeling exercise.   Once the new unit is in plugged into the circuit, probably be a good idea to disconnect the ECM before testing of dinking with the wiring.
Hope you don't have the cold weather that they're calling for us this weekend.  Working on a bus in 25* would be a negative!
My thought of the day.  Now my brain's all tired out.  ;)  JR

   
 


Title: Re: MCI-9 Transmission won't engage
Post by: buddydawg on January 17, 2008, 02:45:41 PM
Did you get your ECM back today?  I'm hoping that it gets you back on the road especially since you have been down for 2 months now. 


Title: Re: MCI-9 Transmission won't engage
Post by: Dallas on January 17, 2008, 02:54:35 PM
I tol' ya we could stick a MT 545 in there!

Just kiddin' Bill, I hope the repaired ECM does the job.

Dallas


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 18, 2008, 08:24:55 AM
Well, the UPS truck has delievered my ECU.   I'm sliding out of work, (glad my boss isn't on this net).  Have some other things to check before I plug it in.

Could there be a end in sight,,,, time will tell,,,,, tick, tick, tick.....


Bill


Title: Re: MCI-9 Transmission won't engage
Post by: redbus on January 18, 2008, 09:08:21 AM
Good Luck. You need it. ;D ;D
Terry


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 18, 2008, 09:38:17 AM
We're WAITING!!     :o ;)

JR


Title: Re: MCI-9 Transmission won't engage
Post by: Dallas on January 18, 2008, 10:02:07 AM

With Hearts all Aflutter!!     :o ;)



Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 18, 2008, 01:20:31 PM

With Hearts all Aflutter!!     :o ;)




Yep!




Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 18, 2008, 03:18:47 PM
THE BUS MOVES

 ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D

I have GEARS,,,, All of THEM !!!!!!! ;D ;D ;D ;D ;D

I've only moved it up on boards, so I could drain a little fluid from the transmission.  Guess WHAT.... It's wasn't the ECU.  I wanted to continue checking out the wiring before plugging in the $800.00, plus two overnight shipping,  either the 221 or the 220 wire corrected the problem.

Still have some fine tuning,,,,the ECU is still flashing the 21 code, the TPS code.  Will play with that tomorrow, weather permitting.  Will take her around the park, if all goes well, for a little ride down the beach tomorrow.

It's not done,,, but there is a light at the end of the tunnel.

fixed  HTML, DML



Title: Re: MCI-9 Transmission won't engage
Post by: bubbaqgal on January 18, 2008, 03:36:35 PM
Hmmmm, seems like I heard someone tell you it was wiring how many dollar signs ago? ;D ;D ;) ::) ::) ;) ;D ;D


Title: Re: MCI-9 Transmission won't engage
Post by: NJT5047 on January 18, 2008, 08:45:37 PM

                             
<<<<O ROLLING OO<<
Very cool that Cat was able to direct the repairs!    ;D
What's the 221/220 wire?  I don't have immediate access to the magnifying instrument that I use to read the little print.  :(
You know, the ECM may still have issues.  I'd bet the return rate is high on ECMs suffering from 'multiple diagnosis"...?
Really glad to hear that it works.
BTW, you may have the TPS misadjusted...or, the TPS is faulty (yeah, the new one), or the ECM takes a few runs to 'calibrate' to the TPS.   Verify that the TPS isn't moving beyond it's range in either direction.  Sammy can tell you how.
Having that bus moving under it's own power is one way to spell RELIEF!!  Gads man.  Fine job sorting that thing out in the winter! 
   
DA  BUS  MOOVES!
   
;D :D :) ::)
Bill, if you ever find yourself up our way, Charlotte, NC, you got a personal invite to drop anchor!  We'll pop a couple cool ones....and then Cat can work on our bus!!   ;D ::) 8)
Cat, ya'll come'on down  the next time you want to stretch that bus a little.  I got an idea....Fayetteville in May, weekend after Mothers Day, party at Wade KOA.  All buses welcome.  Ya'll oughta come on up.  It'll be about time to move...get here early and I'll take care of your parking.  And I don't mind you working on it down by the barn dude.and dudette!  Cat offers management skills!  :o  Gitrdone Cat!
Regards, JR




Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 19, 2008, 06:58:09 AM
JR,

The 220 connects the Shift Selector pin 5 to ECU J2 terminal H.  It is the SS8

The 221 connects the Shift Selector pin 3 to ECU J2 terminal J.  It is the SS2.

As soon as the weather gets a little better, I'm going to go through the set up for the TPS.

Thank you for the invite, you never know when and where I may show up.  Presently looking forward to starting the new job in St. Pete.  If you get down to Florida, let me know.

Bill



Title: Re: MCI-9 Transmission won't engage
Post by: JohnEd on January 19, 2008, 10:15:02 AM
Bill,

I just wonder how many Nuts are putting their sleep meds back in the medicine cabnet about now.  Really glad you got this thing on a "down hill drag" at last.  Happy hunting with the remaining gremlins and KEEP US POSTED.

My very best wishes.

John


Title: Re: MCI-9 Transmission won't engage
Post by: wvanative on January 19, 2008, 03:25:45 PM
Man, what a thread this became, and it showed what the bus community is all about. The best minds, and the best bus doctors, that money could buy. Everyone, and his mother was trying to help solve the problem of a busnut and his stricken bus. I could even picture in my mind the bus on it's top upside down, with all the busnut doctors around it in their white mechanic's coats yelling out "WRENCH, CLAMPS, SCREW DRIVER, STREIGHT 40WT RINGERS LACTATE STAT", and all of us above the operating room looking down on the operation through the big windows of the web, wondering is this bus going to make it. I know many have watched this with quite a bit of interest and great concern. This is a great example of what makes this site the best bus site on the web. Each and everyone who tried to help deserve a great "Atta Boy" 

WVaNative     


Title: Re: MCI-9 Transmission won't engage
Post by: compedgemarine on January 19, 2008, 03:50:01 PM
one of the most interesting things is it shows that with electronics the "stated problem" or code may not be the issue. in this case the TPI circuit is tied into several other things and one can aggravate the other sending you on a wild chase. I think everyone learned a little throughout this thread on how to trouble shoot some of this stuff and to be really thorough in tracking wires and circuits.
glad to see it all worked out as I am sure we could all hear the sigh of relief when it shifted.
steve


Title: Re: MCI-9 Transmission won't engage
Post by: Kwajdiver on January 20, 2008, 02:27:06 PM
The Bus Drives,,, The Bus Drives,,,, The Bus Drives,,,,,   ;D



The problem started Nov 18.  Two months, two days, hours and hours, later,,,, it's fixed. Can't believe this thread has been read 4100 times. 

Went and fueled up  $3.09 a gallon.  Drove it down the interstate for 10 miles.  Wow! Did that feel good.  Looks like I will be able to head to Fred's in Madison, Florida the end of next week.

I adjusted the TPI, need to double check it.  Thought the code had vanished,,, but not so. Believe this is minor.

Thanks to all the busnuts that help me,,, even in the little ways,,,, to help me keep going and not give up.  Thanks to Dallas for coming down to the coast for a week to help for three days.  Thanks to NJ boys and others for all their inputs.  Always gave me something to look up, or at least think about this and that.

Most of all, thank you Sammy   ;D, you folks would not believe how many phone calls between us.  Nights, mornings weekends,,, some from Sammy just to make sure I was hanging in there,  to keep me going.  I know Sammy spent hours of his own time, studying schematics and manual to see which he should send me.  Not only have I fixed a bus, but feel like I have gained a friend.  Thank you Sammy.

As most of you know,,, I start a new job Feb 4th in St. Petersburg, Florida.  I have been a full timer since the day I bought the bus, in Oct 2006.  Once I reach Florida I will start using the bus for weekend trips.  Looking forward to staying close to home and hitting many of the state parks around Florida.  Jack,,, plan to show up your way one weekend.


Thanks again,

Bill    ;D


Title: Re: MCI-9 Transmission won't engage
Post by: buddydawg on January 20, 2008, 02:40:04 PM
Congratulations!  Glad to hear you are on the road again!


Title: Re: MCI-9 Transmission won't engage
Post by: gomer on January 20, 2008, 06:15:10 PM
Bill I want to say thanks to you for not burning the coach or shuvving it over the hill..LOL 
  When you get near Ocala give me a call and I will buy you a cup of coffee and see how many hairs you have left on your head, cause I know you pulled a lot on them..  GLad to hear you are on the road again.
 352-854-9332 home and 352-875-1040 cell.. That goes for all you other nuts too
gomer


Title: Re: MCI-9 Transmission won't engage
Post by: Dreamscape on January 20, 2008, 06:16:07 PM
Good News Bill,

Glad to hear it all worked out finally.

Have a safe trip to Florida.

Paul