99 c5 won't start

[Rich]

Bought a 99 C5 Coupe a couple of months ago. Runs great. Tonight I went out to garage to down load the stock tune with EFILIVE and that seemed to go normal. Ive used EFILIVE for about 5 years on my F body. But now it won't start. And interior lights don't work right. No dome light. Temp control knobs stay lit and gauge lights go out when I turn off ignition. I didn't change tune at all. Just read tune that was in it. I also tried pulling PCM fuse for a minute to see if that would fix problem. Fires up when cranking but dies when key is turned back to run. Any help would sure be appreciated. Thank you

[Tordne]

The interior lighting is all going to be BCM. The PCM and BCM also have a VATS (security) link/relationship so perhaps you are seeing symptoms of a BCM going bad (no personal experience with that). What you could try doing is setting the VATS security to 'None' and flash that calibration to your car and see if it will at least stay running.