Replacing Door Light Switch

[11555wally]

Have an 86 C10 and wanted to check out the door switch that controls the courtesy lights and not sure how to access the back of the switch. Lights door come on when door is opened. There is a fiber panel below the door post area that is held on by push in plastic fasteners and that didn't show me anything. There is a small panel (approx. 3 x 6) that is held on to the inner fender that when unbolted doesn't seem to want to come off. Don't want to force it. Was wondering if anyone has accessed the switch and can tell me how. Thanks in advance.

[TKCR]

The door switch actually screws into the hole and then the wire connects to the back of the switch. So just unscrew the door switch back out of the hole.

[11555wally]

Thank you. I saw the nut on there but couldn't figure out how that would come out without twisting the wire. Pretty neat switch. I have one beige? colored wire going to that switch but it has no 12v to it. I noticed the switch had 2 spades on it. Should there be 2 wires going to it? Thanks

[ray_mcavoy]

Yes, as long as the switch isn't seized up, the center pin will spin free enough to keep the wires from twisting up too much when it's unscrewed.

Two spades & two wires on the driver side switch is normal. The white wire is for the dome light. The tan (beige) wire is for the key-in-ignition buzzer.

[TKCR]

Yes I recently replaced my switches also. There is 2 wires on the left side & 1 going to the right side switch. Mine were rusted on the back side of the switch and the wire had fallen down inside between the walls. I had everything torn out to restore, when I found the wire. I had to fish for the wire to get it back up to the switch to plug in. And while I had it all apart, I wired in more courtesy lighting under the dash and the lighted door sills.

[chengny]

The beige wire (tan per GM) is part of the "key in the ignition" alarm circuit.

The following is probably more than you want to know:

The is a set of contacts in the multi-function switch inside the column that are closed when the key is inserted in the lock cylinder. One side of that contact set is connected to the 2nd spade on the door jamb switch. The other side is connected to the buzzer in the convenience center.

So, if the key is in the ignition and the driver's door is opened, the coil of the warning buzzer is grounded - the buzzer sounds.

[11555wally]

My truck is a Custom Deluxe. There is no switch on the passenger side, just on the drivers side. I have one wire, kind of a beige color, fished for another but came up empty. No 12v on the wire, no ground continuity on the wire. However when I touch the termination of the beige wire and the key in the ignition in the off position and the door open I get the buzzer. I don't have a dome light but I do have two under dash lights that come on when I turn the headlight knob counter-clockwise. Do you think I'm missing a wire for the lights or any other suggestions. Thanks for all your imput. By the way TKCR beautiful interior and lighting.

[ray_mcavoy]

Originally Posted by 11555wally

Do you think I'm missing a wire for the lights or any other suggestions.

No, I don't think you're missing any wires. What you described sounds normal for a Custom Deluxe without the dome light option.

[11555wally]

Are you saying then that it didn't come with the ability to turn on the underdash lights when the door is opened?

[ray_mcavoy]

Originally Posted by 11555wally

Are you saying then that it didn't come with the ability to turn on the underdash lights when the door is opened?

Correct. Without the dome light option, your truck won't be wired to operate the under-dash courtesy lights via the door switch.

But you can easily add that functionality. Just run a new wire from that unused spade terminal on your door jamb switch to the courtesy light circuit. Splice it into the white wire on one of the courtesy lights.

[11555wally]

Thanks for the advice Ray. I think I will run that wire if I can figure out how to get from A to B. Thanks to all.

[ray_mcavoy]

You're welcome! Yeah, fishing the wire in there will probably be a bit tricky.

The courtesy and dome light (when equipped) circuits have an orange wire that supplies them with constant +12V. Those lights are turned on when the white wire is grounded to complete the circuit. So if you want to add additional switches (like one on the passenger side door for example), that would also get connected to the white wire.

[11555wally]

Thanks Ray. I just went out and looked at it and I have one light under the dash (I thought there were two) located just left of the glove box with a orange and white wire going to it. Maybe some one will see this and chime in with the best way to get into that door post.

[TKCR]

Up under the dash on the left side, there is a little rubber grommet with the wire going into it that goes to your door switch. If you disconnect it from the door switch, you can pull it out and tie into it and then you'll just have to fish for it through the door switch hole and pull it back. And then reset the rubber grommet.

There is only one courtesy light under the dash, but thats where I added a set from LMC, to make 3 (and I put LED bulbs in all 3). I just tied into the wires under the dash where the current light is. The Lighted door sills, I tied into the door switch wire. I had to pull them out and then fish them back to the new door switches. I wish I had taken pictures when I was working on that project, but I also had the dash completely tore apart, so all the wiring was pretty visible.

[11555wally]

Thanks for the info. You sure did a nice job on yours.

[TKCR]

Originally Posted by 11555wally

Thanks for the info. You sure did a nice job on yours.

Your welcome!! And Thank You for the compliments. It was a winter time project, restoring the dash and ect. Can't wait to get her out for a drive, which I wanted to today, but the battery was dead (really dead) it didn't even want to start with the Battery Charger. I was being impatient, so I gave up. It's out there charging now in the garage.