I am working on a 99 S-10 pick up. I changed everything to add the factory fog lights. I took it to a dealership to reprogram the BCM so the foglights would work. I was told by the dealer they reprogrammed it but they still wouldn't work that it was a possible fuse block problem. I found another BCM with the foglight option from a 99 blazer plugged it in the lights worked properly but the truck won't start with this BCM in it. The dealership told me the BCM does not control the starting of the vehicle. Im thinking the dealer is wrong because the passlock is in the BCM Correct? I changed BCMs in 2 blazers I had years back with no issues. Am I missing something here?

 

Dealer messed up twice! First time was programming, second time was saying the BCM doesn't control the engine. You're correct, Passlock is controlled by the BCM. If it detects a possible theft situation, it will not authorize the PCM to activate the fuel injectors. Better get your money back from the dealer and find one that knows what they're doing.

 

Unfortunatly that's the only one close. Now my understanding is that I can take the correct BCM in the truck to a dealer they can program it so the factory fogs will work. Is this correct or is it once its programmed it cant be reprogrammed. I've heard both.

 

The BCM can be reprogrammed as many times as you want. Bring the BCM and the VIN to any GM dealer. If they know what they're doing, that's all they will need.

 

Thanks. Now just to find a deal that will just turn on the lousy fog light command.