You can try the security relearn and see if that helps with the starting problem, but I don't think it (Passlock) is related. To do the security relearn turn the key to ON and leave it there for 11 minutes, then turn the key to the OFF position and leave it there for 30 seconds. Repeat this 2 more times for a total of 3 cycles. (ON 11min/OFF 30sec/ON 11min/OFF 30 sec/ON 11min/OFF 30sec). Then start the car.

I'm thinking more along the lines of MonteMan92. I've read on more than one occassion about a bad ignition switch causing dash lights to flicker and difficulty starting the car. I think I would focus on it before the BCM. A salvage yard BCM will need to be programmed to your car in order to work (the same as a new unit) so unless you are positive that the BCM is the problem I'd hold off on buying one.

 

I had some problems with mine, A dealer replaced my bcm and I had no more problems knock on wood. I was fortunate that it happened just right after I bought it so it was fixed for free.

 

The used bcm is only twenty dollars and they have it graded in 'A' condition. Given the per hour rate shops charge for trouble shooting I thought this might be worth a shot. I'm not worried if everything works, as long as it consistently starts.

If the used part fixes that I'll order another bcm from rockauto.com and then take it to the dealer for programming. The Chevy dealer wants about 500 to replace the bcm and that doesn't include diagnosis. They will program one for about 90.

If the used bcm will function well enough to confirm that is indeed the problem it would cut my repair bill by at least half. I'm hoping someone can tell me if the used bcm would allow the car to start. I don't care if the radio or power windows or whatever don't function with it.

Thanks for the replies!

 

Better be careful, the older bcm's had problems. The new ones are suppose to be better per gm mechanic, he just wanted to sell me a new one probably lol

 

The salvage yard bcm would only be for testing purposes. If that got the car to start reliably I was going to order a new one and then I would only need the Chevy dealer to do the programming. Since the used part is only 20 dollars I figure its worth a shot.

 

Can't go wrong with $20, best of luck on getting things figured out.

 

my god what a nightmare

 

what about the New Rockies Bypass? does it actually work?

 

I am currently chasing down a similar problem on a 2001 MC SS. The interior lights flash rapidlt, traction control ,ABS,low fuel, and other strange things. The big issue is it will not start. If I leave the ignition on for about 20 minutes it will start. Otherwise it does all the above. I thought it was the security system. I replaced the ignition switch but it made no change. The car would not even allow the relearn process to finish. It would act right on the first key cycle and then the interior lights flash and the dash lights up with all the above trouble lights. The security light will not go out on the second key cycle. I have come to the conclusion that the BCM is so messed up that it wont even allow the new ignition switch to do the relearn process. One weird thing I did was I removed the ignition switch and disconnected the pass lock sensor and put the original ignition switch back in without the pass lock sensor plugged in. The car started 3 times. Then on the 4th try no start and the horn started sounding on and off. I had to disconnect the batteryt o make it stop. I've worked on autos for 35 years and never saw anything like this. A new BCM and a trip to the dealer to have it programed is the next step. Wish me luck. I beleive I need some.

 

Replaced BCM and installed a bypass module for the security system today. The car allowed me to do the relearn process for the bypass module. After that the car has started 5 times and all systems seem to be happy for now. The bypass was from a company called New Rockies. It worked! Didnt have to take it to the dealer. Amazing!.