Instrument panel lights not working

CBLUEDOG

MEMBER
2004 CHEVROLET TAHOE
5.3L
V8
2WD
AUTOMATIC
200,000 MILES

I took truck to emissions which I failed unknowing that my ECM fuse was blown. I replaced the fuse and viola my warning lights started working (was unaware the weren't). But now my cluster lights don't work. I replaced my headlight dimmer switch, checked a couple a fuses and still nothing. When I check the lights out of the truck they all are working but for some reason once plugged into truck there nothing. All my other dash lights work, interior lights and brake lights too. Any ideas what could be the issue?

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,709 POSTS

Welcome to 2CarPros.

When you say you check the lights out of the truck, they work, but then don't work when plugged into the truck, I'm not sure what you mean. How are you testing them? Is it only the cluster lights which are the issue?

I went through a few wiring schematics on this vehicle. Power is supplied via the body control module (BCM). See Picture 1. I circled the supply (red wire) and the dimming circuit.

Now, the one common thread I see is ground location. I need you to check the grounds. See Picture 2 for color and location.

Check these and let me know what you find.

Joe

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