Did you ever get in touch with Jack's ECM guy?
We've just been back in cell phone coverage for a day. It's on my list, but not high priority (I've lived with this issue for years; another few days isn't going to make a difference).
Maybe the guy that Don referred you to just lost your contact info. Maybe???
Maybe he did, but no excuse now: I emailed him after Don posted that. So far, have not even received an acknowledgment of my message.
Did you ever get any response to your solicitation for a replacement ECM to "try". ... Might have better luck sending yours to a bus with an operating system to have them "try" yours.
No I did not. "Sending" my ECM anywhere is out of the question -- we drive nearly every day, and we could be called to a disaster any time. We can't have the bus "down" for an indeterminate period with its ECM out. This has to be a drive in, try it, drive back out sort of exchange.
That suggestion that you upgrade to a DDEC III with a kit from DD sounded like it had merit. Was the total price under the $2K that you mentioned?
Upgrading to DDEC-III is upwards of $4,000, with virtually no benefit (other than maybe fixing this problem).
1- There is a battery that keeps the accumulator portion of the DDEC alive to remember total values as they run on. This is different from the portion that keeps the programming stored. (There is supposed to be a code to identify this low voltage but he said it doesn't always show-code #53). Trip fuel, PID 182, and trip distance, PID 244, are not showing any increase.
Actually, the last statement I've found out is not quite accurate. PID244 shows an increase only when there is zero fuel flow ie when coasting downhill for more than a tenth of a mile!
The battery was supposed to be non-replaceable. I know mine is 19 years old.
OK, now this explanation makes sense to me. However, when I have asked around about this, and researched it on-line, what I have been told is that the memory battery did not come along until DDEC-III, DDEC-II did not have one. That said, it's hard to know whom to believe in this regard. If you discover this to be true for sure, let me know. I am more than happy to take a soldering iron to the board and replace the battery.
2- The PROM responsible for the accumulators inside DDEC2s was never "secured" in the early versions and had a habit of vibrating partially out of its' socket, causing strange readings that were not predictable. This was particularly applicable to engines that were canted with the DDEC mounted vertically, allowing the vibes to shake it out. Apparently DDEC 2 later version and newer are solidly attached. Mine is a "transit package" that is tipped 43 degrees, DDEC perpendicular to the ground.
This one I knew about. There is actually a little clip for it that came out as a retrofit to fix this issue, and my ECM has been checked for this clip.