E38 Camaro Checksum failure

[horst]

Keep getting "Checksum Failure" error $06ff all the time. Tried older files of this car as well, not good.
I have a spare PCM, wanted to Flash this for test, it gives me the same Errors.
I have done quite a few with this V8 Version, never a issue. Also updated to the latest, still the same.
What can i do? Car is not starting anymore, but i still can Flash it (but get the error at the end)

[GMPX]

Try this file instead. Looks like it has had a tuner on it before that is causing some issues.

[horst]

Correct, tuned with a handheld before, but since it was done i already modified it several times with Efilive and never had a problem.
That was last summer with some older V7 revision. And now it suddenly crashes. Will there be a permanent fix in the future or do i always run the risk of locking a car down?