What happens when your bcm is bad in your 2002 buick rendevou?

CHAOS :)...............The prblem with BCMs is they control everything electrical in the car. so if they go bad they make the car act possess. it can be lights staying on, rear hatch opening for no reason, alarm going off, windows refusing to work then start working. I havent had any problems with my BCM knock on wood but ive hear the horrors stories. if you car does start acting odd one thing to try is to reset the computer. disconnect your battery for 5 minutes and connect it back this reboots the BCM and solves the problem but a bad BCM they will just keep coming back. The BCM can only be replaced by the dealer unless your mechanic has the Tech 2000 but porolly not since they are thousands of dollars, they have to be new. BCMs cant be reprogrammed once they are programmed. im not sure bout the options but the vin is programmed in and cant be changed, and i hear they can run 4-800 dollars for the repair. Hope this helps