dome light switch

[magnethead]

ok, my dome light only comes on if I twist the switch...I'm not sure if the door jamb switched are unhooked or what....where do they come out the kick panel from, and does the wire for the light follow the roof marker wire up the A post or what?

[ElGracho]

The most likely problem is the pin switch in the door. They get dirty and don't make good contact to ground (It grounds when the door is open). This link goes to a simplified wiring diagram:

http://www.gmtrucks.org/component/op..._light_circuit

[wedgemon]

Mine used to come on when I pushed in the Cig Lighter. These trucks are notorious for odd cab wiring.
- Dave

[magnethead]

ok, let me re-word that.

Where SHOULD the wires run from the jamb switches to the main switch and/or lights as opposed to where did the factory put them. Are they out in the open or do i have to remove the kick panel and all that other nonsense stuff?

[84 400]

Wow my old 85 used to have the same problem! ha ha ha the door pins wer old and rusty and seemed to be the culprate but i never replaced them. does yours not have the wiring ?

[magnethead]

i'm banking that mine are rusted, considering the panel they connect to is cancerous. But I also want to know where the factory runs the wires so if need be, i can rewire it my own self so I know it works.

Also, is there a way to modify the circuit at all to turn on if the back doors are opened?

[84 400]

wow your lighting crazy ha ha ha. i wish i had some answers for you but electrical was never my thing. i would imagine that you could mimik the front idea and drill holes and add the push pins that are in the front. did you ever get the other idea to work? Also what are your plans for the truck? i may have already asked that. I take it that this truck is a worker as i can't imagine why anyone would want to feed a 454 dually. Well i take that back i actually really like your truck and even though i have no need i would love to have one like it and then find a need for it. Any futer plans?

[Hoods69BadBowTie]

I have the same problem with my Cavy and I have been messing with the door pins to no luck. As for your other questions I have no idea, I understand some of this electrical stuff but someties I just confused. LOL.
-Later

[boxrodz]

Originally Posted by magnethead

...
Also, is there a way to modify the circuit at all to turn on if the back doors are opened?

Sure.
Borrowing the GMTrucks diagram that ElGracho posted, tap into the white wire on the front door switch and extend a wire to the door switch for the rear doors. Ground the second terminal of the rear door switch just like the Ground terminal on the front doors. See 'revised' diagram.

[ghetto_superman]

i cant tell you much, cause its been a few years since i did it, but i wired a few of those jamb switches into my 68 cab so the dome would turn on with the doors... what i can tell you, is that the switches arent on the positive, IIRC(keywords!) thres power going to the light all the time, but the ground is interrupted by the jamb switches.. it seems confusing, but i test lighted the crap out of everything and after brainstorming stuff for a while i ended up with a system thats pretty fool-proof. as long as you have a basic knowledge of DC power.. you should be able to figure it out.

and who knows.. maybe that info wont help you out at all because maybe the wiring i started with was just GM factory JACKED up anyway!!!
-good luck!

[beaterC10]

The wiring from the jamb switches runs through the door jamb up to a grommet in the dash. The grommets are located near the acces hole for the upper hinge attaching bolt. To get access to the grommets you will need to remove the dash cluster and glove box.

The wire from the pass side runs through the dash in the harness used for the cig lighter, courtesy light, and glove box light. The driver side wire runs to the fuse box and plugs into a connector in the main dash harness.

The wires from the dome light run down the post behind the drivers seat and under the sill plate to the fuse box. There should be a connector in the double wall of the cab that connects the dome light wiring to the wiring going to the fuse panel. If the door jamb switches are not the issue look at the dome light wiring, it takes a beating on a rusty truck under the sill plate. The dome light wires are orange and white.

[magnethead]

thanks, i'll fool with that sometime today hopefully.

yup, this was a work truck. 348,000 (we think?) miles and counting. Give me 10 grand and i'll show you my plans (it would make stacey david drool probably)