I have been having some electrical issues lately. little background:
My cars battery would drop to 11.75 volts when turned off, needed a jump to get it started, once started, the batt. voltage would stay around 14.7/14.8 at the battery. I decided something was draining the battery when I turned the car off, so I pulled everything electrical I had in it. (Alternator about a year old, and just bought a new optima yellow top after I removed everything.)
I removed, the alarm, remote starter, my amp, everything electrical that didnt come with the car. I basically rewired everything back to stock. However, when I took my car out for a drive, it started up fine, then drove around about a half mile, then my Theft light went on, along with the service light. I decide to turn around and head back home, then my abs light, brake light, check gages light, low fluid light, etc. turn on. My gauges would spurratically all drop to 0, and the turn signal lights on the dash would both come on real dim. Basically all the warning lights would spurratically shut on and off the rest of the way back home. When I pulled in front of my house, I shut it off, started up fine again, about 2 blocks of driving, same thing.
So, I rechecked all the connections, and I just noticed that the BCM has a black thin gauge wire coming from the inside of it. This wire is connected to the printed circuit board on the inside, and nothing on the outside. Does anyone know if this wire should be hooked up to anything, and if so, where? I will go take a picture of it in a second.
Here arte the pics:
i assume it might be a ground?
Oh, check your ground to the battery tray. It's a common one to corrode and cause exactly what you described. There's also a pair of grounds on the frame rail under the battery tray, and you could also check the ground on the transmission case (by the starter)
Lenko, John Lenko wrote:It's called an antenna 
heh. Beat me to it.
And if you're scratching your head and wondering why there's an antenna on your BCM... it's for the keyless remotes.
Thats right, I forgot the keyless remotes operate through the BCM. Time to go check those grounds.
