C3500 interior light electrical.


Registered User
Jul 1, 2020
Reaction score
I was wondering if anyone happen to have a electrical diagram of the interior lights.

the previous owner did a hack job on it and it’s causing me to scratch my head.

the copper completely rotted out of almost every wire and just crumbled in my hands.

I got all the bad wire removed and was about to start splicing things back together but I realized if I put it back how the previous owner had it the dome light will never turn off.

I got every wire figured out except for 5 or 6 of them.

I got a black ground wire. (Not entirely sure what it’s for but it’s pretty Obvious where it goes)

2 orange wires (one is always hot the other goes to a relay someplace under the dash and I hear it clicking when I touch them together how the previous owner had them wired)

3 white wires (one is always hot, one appear to turn the lights under the dash on when power it applied and the orange wires are together. And one appear to make a relay click under the hood someplace. 2 appear to of been tied together and the one that activated the relay was on its own going to what appears to be the same place as the black wire.

No wires appear to be affected by the door switches at all.

I got 2 new front door switches. When I check the wire I got ground coming in on the black wire and going out on the purple and white. (With all other doors closed)

I just noticed while I was writing this the door chime is missing. Could that be why my dome lights don’t work? But if it does I still would need to undo all the Ghetto wiring the previous owner did and put it back to stock.


*Edit* I found a white wire with a blue stripe going up to the middle dome light. No clue where that’s so post to go.

also that white wire that goes to the relay under the hood apparently was connected to a yellow wire in the very back of the cab. In less Chevy’s are different in my experience wires don’t normally change mid strand like that in stock wiring. So that has me a little baffled.

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach
Last edited: