I am working on a 2002 blazer for a friend. It had been neglected by their daughter and then sat in their driveway for a few months. After doing a full tune up and replacing all filters I got her running, with a jump start from my car. Had it running for a couple hours. Told them all was well. A week later they had not driven it but it wouldn't start. They were thinking fuel pump because it would run if they poured gas down tb. I get there and battery is toast. Put a new battery on and the headlights, dash lights, abs module etc come on by themselves. The security light is staying lit all the time (even with the key removed). I tried the passlock relearn, but the security light will not go out at all. I'm think ignition switch, but the abs, headlights etc coming on throws me for a loop. The radio keeps giving an error message and clicks/resets also (CALL ERR). All this happens with no key in the ignition!! This blazer was a stripper from factory, no cruise, electric windows, locks, or anything. Any help is much appreciated.

 

this is going too sound stupid but you might give it a try anyways - key off, ***. off, unhook both the battery terminals - neg. first then the pos. - leave unhooked for five or ten min - when reinstalling them have key off, ***. off, - then install the pos. first then the neg. it keeps from surging the computers

 

I'll try just about anything at this point. Although we were talking earlier and when I had it running that day I was using a different key, possibly an original GM key. The one I have been trying to use since it wouldn't run for them is a copy. I am wondering if the first key was an original and maybe they tried to use the copy with the dead battery and that has freaked out the passlock? They are looking for the other key now.