• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

Body control module

Tommy W.

New Member
Messages
1
Reaction score
0
Location
Aurora, Co
Have a 2009 Chevy Silverado 2500HD Duramax. Installed 2 brand new batteries and overnight was unable to start. Is it possible that the BCM is causing my batteries to drain out and if that is the case, what would be the best scenario to find out if my BCM is causing the problem.
 
Probably wrong forum to get the most answers.
But I would look at the alternator first. After charging the batteries back up and it sits for a bit, see if it feels warm.

Sent from my SM-G892A using Tapatalk
 
I cant imagine a bcm being the culprit and not having things not work in the truck. The module itself draws no real power to operate when the truck is off. It is usually something on or a short pulling the power.

My suggestion:
Key off

Remove secondary battery cables and keep the positive cable isolated from ground.

Remove positive cable from primary battery and read amperage from positve post to that positive cable. Place meter where you can see it from fuse block.

Remove and reinstall every fuse and relay one at a time until the large amp draw is gone. Remember when you do the interior light fuse that your door is open...(I made that forehead smack before)

If you find them- post it here- what circuit and draw.

Chasing it this way is not hard, just takes a little time. Just remind yourself a shop will charge you $200 for this task alone.
 
Unable to start is pretty vague. Dead batteries assumed. May want to verify this as starter failures or a bad cable connection can be similar.

When doing an amp draw there is a delay of a few min as all the modules are awake and then go to sleep. Onstar is famous for not shutting down. The dome light will shut off eventually as part of the battery save function: Thus is for sure when the amp draw should be the lowest.

Phone charger plugged in or other items in a 12v always on socket?

Does this have the heated washer fluid, burn the truck down, option? And was the recall done to remove it?

Trailer wires like the battery charge wire could be shorted and cycling the 30A breaker.
 
Back
Top