Wiring diagram needed for the BCM and the doors, including ajar switches and actuators, driver seat heater and motors and the wiring in.

AIRICKZOWPA

MEMBER
2003 CHEVROLET TAHOE
5.3L
V8
4WD
AUTOMATIC
245,000 MILES

Former auto tech but been away for 15 years. My "Passenger Rear Door Ajar" message is always displayed. My driver seat no longer moves and no longer heats.
I have checked the basics, fuses, connectors etc.
I am looking for accurate wiring diagrams for my vehicle listed above, specifically for the BCM and the doors, including ajar switches and actuators, driver seat heater and motors and the wiring in between it and the BCM as well.
I suspect my BCM is shorted internally, but I don't have the money to just throw one in and have it programmed in the "hopes" that it fixes my issues.

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
48,584 POSTS

This sounds like the DDM is out, but here is the BCM and door lock wiring diagrams so you can go over the outputs and inputs. Also, did you try a CAN scan which can help give you the codes for a bad DDM? You can get a CAN scanner (Controller Area Network) which will work on most cars from Amazon.

Here is a video to show you how:

https://youtu.be/u-4syLc-ifQ

As you can see the BCM does not have much to do with the door locks. Check out the images (below). Please let us know what happens.

Images (Click to make bigger)