Error: $0537

[nrmskate]

I am getting an error on my 03 LB7 when I try to read in my ECM from my AutoCal. I have tried Alt Keys, Assume ECM is locked, Try Additional unlock methods, etc. with no luck. I have my trace file on hand and my license backup file. What should I do from here?

[comnrailpwr]

Pull radio, info, radio amp fuses, check assume lock may be faulty and un click high speed. Sometimes it works.

[GMPX]

Also think about any aftermarket equipment that may have been wired in to the data bus, these always cause problems on the LB7 & LLY.

[nrmskate]

I have already tried all of the things you guys have listed. I've also tried bench flashing it with no luck, so that definitely rules out any electrical interference.