Body control module
 

hey does anyone know how to check to see if a bcm is working or not???

Do your lights come on? If so, your BCM is fine... I replied in your other thread, and it's not your BCM but your RAP module that is going bad. Replace it and all will be well.

ok thx but ant a rap works when u take the key out the it stays on for 10 mins and if its the rap i cant find on any where for a 99 camaro ive tryed ebay and searched places anywhere to look?

In '96+ models, the RAP is built into the BCM. 1996 was the first year GM put the BCM in the F-Body. Before that, there was a RAP for keeping accessories running after you turn the car off, and everything else was simple relays.

I know it's been a while since this question was asked, but I found it in my search for my own BCM issues... Hope this helps someone.

whats a BCM, and whats it do? all news to me

Most newer cars (OBDII) use a BCM. The BCM controls most of the electrical circuits in these cars. This was done to save wiring and to allow diagnosis of most electrical problems using a scan tool. Unlike most general purpose scan tools that only handle standard power train trouble codes (P codes) this scan tool can read manufacturer proprietary codes which car makers try to hide from the public.

wow, but how can you or me be able to scan and read a bcm if its only for manufacturers?

You need a professional type scanner such as SPX/OTC, factory scanners such as the GM Tech III, SnapOn/Solus, etc. These tools can cost as much as good used car. SEMA is lobbying Congress to get regulations passed to make the manufacturers publish all information and make it available to the general public.

A tech 2 is about $2000 with an updated card through current year.