Killed two GenIII PCMs in a row.
I'm finishing a gen111 5.3/ 60E swap and I've lost two PCMs during reflash. The first was during a cal only flash, second was during full reflash (replacement PCM). In both instances all appeared normal until the software attempted to reboot the PCM. During both failures I noticed that the software attempted the reboot 7 times before saying ok. Turn the key off for 15 seconds and attempt to start the engine.
The fuel pump only primes for a split second (unlike the usual 3 second prime), no start and no communication. The scan tool does not recognize the PCM, no read or write in the tune tool.
I've read the threads returned from searching "dead" and it seems that PCMs falling into a "dead poll" state is not too uncommon but my symptoms don't appear to be those of dead poll. When trying to read or write, the software is unable to determine the "status" of the PCM.
I should mention that I have driven this vehicle before I began editing the original cal. In fact I was able to do three or four cal only reflashes before the first PCM failed. Today, I installed a used replacement PCM and attempted to full flash it once and it failed. On the initial KOEO, the fuel pump primed normally so I'm certain the PCM was in working condition before the full reflash.
I'm two PCMs and licenses deep and can't afford to try again unless I find something that may have caused these failures. Also the orange LED on the FS V1 does blink during communication attemp, however it is something like 1-2 times per second instead of 4.
What can I do to ensure a successful third attempt? Bench top harness? Thanks guys! This is getting costly!
