When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
My dome light works when I open up the passenger door but doesn't work for the drivers door. I replaced the door switch but that wasn't the problem. Do the passenger side wires from the switch connect right to the drivers side switch then to the fuse box? Also, the headlight switch when I turn it to the left also does not turn on the dome light. Is it suppose to? Its working fine in turning up the dash lights. . Can someone help please. Thank you
Its a 1977
Last edited by garykuter; Jun 7, 2021 at 05:25 AM.
I don’t see what year car you have, so my info below is based on my car (77) and experience with other GM cars. Yours may differ.
The dome and courtesy light circuits are odd on our cars in that, unlike the other lighting circuits, they always have power and the switches provide the ground to complete the circuit.
My initial guess is that your driver door switch doesn’t have a good ground. Check to make sure the threads in the door jamb where the switch screws in are clean. You might also try removing the switch and grounding the white wire directly with a jumper to see if that lights up the dome.
In answer to your other questions - yes, the passenger and driver switches are connected with the white wire, but not at the fuse box. The orange wire at the light is the hot lead from the fuse box.
The headlight switch should turn on the dome light when you turn it all the way left. It may be related to the other problem but I’m not seeing how. It might just be a bad switch.
Your best bet is to get a good wiring diagram for your year to help you track down the problem. Hope this helps.
The ground goes to passenger side first then over to drivers. Probably where the problem is.
Correct. The orange wire(s) inside the cab provide 12v power to bunches of things. The white wires run from the various interior lights to door switches and the courtesy light timer that provide the ground reference for the lights.
I'll post what I've done with that on the "what have you done today" thread.
Thank you it does. There is no juice at all on the drivers side wires. So, i can just run a new wire from the passenger side switch to the drivers side one. I'm sure theres a break in the wire somewhere thats why its not working.. Thanks again
Last edited by garykuter; Jun 7, 2021 at 05:31 AM.
The door switches only serve as a path to the bulb(s) ground side on the Clock/Cigar/Courtesy circuit.
There were 2 different wiring designs for the 77.
One with delay, one without.
The door switches also serve as the Anti-Theft circuit and there is a difference in that circuit early vs. late build 1977.
If you need to bypass the delay timer, disconnect the 2 connectors labeled C121 from the delay timer.
Reconnect both to each other. The delay timer is now out of the loop.
1977 Clock/Cigar/Courtesy drawing.
dome light
