Cm870 tuning issue needs some help

[Sledpuller]

(02-03-2023 )Rawze Wrote:  I was asked about this earlier this evening. I know that different programs, etc. were tried, so it is not likely the program itself, however it can be the laptop or other hardware. Using a different computer, different adapter (cummins instead of nexiq) and/or different flash method might reveal the issue. Things like switching to the J1708 (or J1939 can bus #2) thru the dash etc. instead of a bench harness, etc.. sometimes yields different results.

some thoughts...

* anti-virus software or other USB scanning software on the PC will interfere with flashing an ecm.

* Sometimes having an older cummins inline-5 adapter instead of a nexiq solves these kinds of issues ... I have seen this before.

* Wrong J1939 terminating resistance will cause the flash to fail.

* is it failing in exactly the same place every single time?? or randomly?.

* are there a lot of re-send errors before the failure?.

* have you tried forcing it into run mode and flashing it with CT? .. watching how many retries it does along the way?.

* Is engineering mode turned on?... It should not be for flashing one.

--= and of course, it could be a block of memory in the ecm that is simply going bad too. ==-
* How old is the ecm?. If it is more than 8+ years old then buying a new ecm is not a waste of moneys... as it has lived longer than its design life any ways.

It’s failing at the same point every time no matter if we use the bench harness or the data plug in the truck. 70% every time.
We tried switching to j1708 but it would not connect to the Ecm.
I don’t know how old the Ecm is.
No errors that I see before failure.

The rest of your questions I don’t have an answer for as I’m not well versed enough to understand and answer correctly.
Thanks