Major Battery Drain

[kentrx1]

have a 2004 z71 with 5.3 engine. yesterday i got up to a dead battery(only 6 months old). carried it to advance auto, they checked it, charged it, and everything checked out. this am it was weak again. drove vehicle there and they checked everything again. battery, starter, alternator all checked fine. did notice that even with key out there is a clicking noise on the passenger side of the engine compartment. would really appreciate any ideas!

[sonjaab]

IIRC there was a TSB out there for the gmt-800s for either a RAP module

(retained acc. power) or BCM replacement for a battery drain issue.

 

This is from 2003 and may apply:

http://www.gm-trucks.com/forums/index.php?showtopic=14362

 

#02066 -- Battery Drain

 

involved vehicles are certain:

2003 Chevrolet Silverado, Tahoe, Suburban; 2003 GMC Sierra, Yukon, Yukon XL; 2003 Cadillac Escalade, Escalade EXT, Escalade ESV

Equipped with Quadrasteer (NYS), Autoride (Z55), or Vehicle Stability Enhancement/StabiliTrak (JL4)

 

December, 2002

Dear General Motors Customer:

 

We want your experience owning your 2003 model year Chevrolet Silverado, Tahoe, and Suburban; 2003 model year GMC Sierra, Yukon, and Yukon XL; and 2003 model year Cadillac Escalade, Escalade EXT, and Escalade ESV vehicles equipped with Quadrasteer, Autoride, or Vehicle Stability Enhancement/StabiliTrack to be better than any other you've had ... which is why we're writing.

 

We have learned that your 2003 model year Chevrolet Silverado, Tahoe, and Suburban; 2003 model year GMC Sierra, Yukon, and Yukon XL; and 2003 model year Cadillac Escalade, Escalade EXT, and Escalade ESV vehicle may have the potential of exhibiting a battery drain condition. An anomaly in the operation of the steering wheel position sensor may keep the Body Control Module (BCM) from shutting down when the key is in the OFF position. The resultant 3.5 amp draw/load on the battery could possible discharge the battery to the point where the battery will not have sufficient amperage to start the vehicle.

 

What We Have Done

We've sent a new BCM calibration to your dealer so that your vehicle can be reprogrammed to ensure that the BCM shuts down when you turn the vehicle off. This service will be performed for you at no charge.

[gmtech4]

is there another thread about faulty bcm's? i have spoken with a couple other chevy owners and have heard about the cd player shuffling, door locks locking and unlocking - or not working with the key fob, the vehicle not starting, lights flashing - this used to happen very infrequently and usually when starting the vehicle....however, it occured the other day when i was driving down the highway @ 65 mph - i have read other forums about it being the bcm - any input or direction on this issue? i have a 2007 2500HD 4wd silverado

Take it to a shop to diagnose it not the Internet to guess ,

 

It's a major expense , why guess ? Have a scanner pull any codes , not DYI in any case

[kentrx1]

turned out to be a short in the passenger power seat. was told it would be $800 to repair.....so i just had it unplugged. can these motors be rebuilt?

[Sweetsail]

is there another thread about faulty bcm's? i have spoken with a couple other chevy owners and have heard about the cd player shuffling, door locks locking and unlocking - or not working with the key fob, the vehicle not starting, lights flashing - this used to happen very infrequently and usually when starting the vehicle....however, it occured the other day when i was driving down the highway @ 65 mph - i have read other forums about it being the bcm - any input or direction on this issue? i have a 2007 2500HD 4wd silverado

[gmtech4]

doubt it,its a google away if ya know the company who made it ,junk yard search it

[GasHog369]

sounds like a relay of some sort clicking .....

[kentrx1]

sounds like a relay of some sort clicking .....

 

 

but what would keep going with key off?