BCM wiring diagrams

2004 PONTIAC GRAND PRIX

255,000 MILES • 3.8L • 6 CYL • 2WD • AUTOMATIC

SCOTT BOWKER

MEMBER
1 POST

Started with left turn signals, bulbs are. now doors wont lock or unlock,windows wont go up or down ,sunroof still works ,power seat wont move ,dash through up traction control wont work. I'm stumped?

May 5, 2020 at 2:41 AM

KASEKENNY

✓Experienced Mechanic
18,907 POSTS

Did all of these items stop working at the same time? I am not convinced this is all one cause but if it were, it would be the BCM. I attached the info about the BCM. As you can see with the wiring diagram that the systems are run through the BCM. Clearly we will need to check fuses to the BCM but this would be the common denominator with all these items.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Let's check for codes and then go from there. Thanks

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