Door Jamb switch wire - where does it travel to?

[blindbug]

I’m trying to fix my under-dash courtesy light so that it comes on when the door is opened. I’ve pulled the jamb switch from the drivers door (I don’t have one in the passenger jamb). There is an orangish wire coming out of the switch, and only that one wire. It travels up and then through the kickpanel area and around to beside the fuse block where it has a terminal and hooks up to another wire which looks like it is going to the back of the fuse block. You can see it to the left in the picture.

I’ve manually shorted he wire that attached to the switch against the body, but that doesn’t seem to activate my under dash light, which is not what I expected. My understanding is that the switch just grounds the light also that it can light up.

Any help on what I can check or if I’m just chasing a lame goose is appreciated.

1986 Chevy C10 Custom Deluxe. No dome light, no passenger jamb switch.

[mongocanfly]

yep...all the switch does is make the ground leg of the circuit...hot to the light and ground to the switch...
my custom deluxe has dome light and switch on passenger door...I thought they all had dome lights....guess not

[blindbug]

So should the wire coming from the switch go to the light, or to the fuse block? I feel that it eventually goes to the headlight switch, but I’m not sure. I replaced the headlight switch recently, so it should be good. When I turn the switch counter clockwise, it DOES turn on the under dash light.

[mongocanfly]

I'm not sure where all it goes but it eventually gets to the light...you might try a google search of wiring schematicsand follow the wire path..

[4x4k30]

the door jam switch works when the jam switch pops out it grounds its self which is spring loaded to the back of the switch which is hot its just one wire that goes to it to the fuse box then to the headlight switch... with the door closed try to turn the headlight knob all the way to the left it should click that powers both the under dash light and the lamp in the cab if want to just buy 2 new door jamb switches and wire them both to a single hot wire and you should get the light to come on .the light should have a wire coming into it from each side .

[mongocanfly]

"if want to just buy 2 new door jamb switches and wire them both to a single hot wire"

^^^^whatever you do DONT hook a hot wire to the door switch^^^^
....
the door switch is a ground...hook a hot to it and you'll have a dead short and melted wires....

[mongocanfly]

maybe this'll help....
http://67-72chevytrucks.com/vboard/s...d.php?t=611743

[ray_mcavoy]

Originally Posted by blindbug

1986 Chevy C10 Custom Deluxe. No dome light, no passenger jamb switch.

With no dome light, there will only be 1 tan colored wire going to the driver side door jamb switch. That tan wire is for the buzzer that sounds if you leave the key in the ignition when you open the door.

The courtesy light under the dash has an orange wire that is live all the time. And a white wire that runs directly to the headlight switch. Rotating the headlight switch knob all the way counterclockwise closes a set of contacts in the switch that ground the white wire. That completes the circuit to ground and turns on the courtesy light.

To make the courtesy light come on with the door open, you need to wire it up so the door jamb switch can also complete the ground on the white wire. That can be done by simply splicing into the white wire and running a branch over to the door jamb switch. But don't splice it into the tan wire for the key buzzer. Instead, there should be a 2nd (currently unused) terminal already on the door jamb switch just for this purpose. If not, get a replacement door jamb switch that does have 2 terminals.

[blindbug]

Originally Posted by ray_mcavoy

With no dome light, there will only be 1 tan colored wire going to the driver side door jamb switch. That tan wire is for the buzzer that sounds if you leave the key in the ignition when you open the door.

The courtesy light under the dash has an orange wire that is live all the time. And a white wire that runs directly to the headlight switch. Rotating the headlight switch knob all the way counterclockwise closes a set of contacts in the switch that ground the white wire. That completes the circuit to ground and turns on the courtesy light.

To make the courtesy light come on with the door open, you need to wire it up so the door jamb switch can also complete the ground on the white wire. That can be done by simply splicing into the white wire and running a branch over to the door jamb switch. But don't splice it into the tan wire for the key buzzer. Instead, there should be a 2nd (currently unused) terminal already on the door jamb switch just for this purpose. If not, get a replacement door jamb switch that does have 2 terminals.

Holy hell... I think THIS is why I can't get the courtesy light to activate on the door switch. I do have a single wire coming from the switch, but I do not have the buzzer in my truck. I checked everything I could and everything seemed to work good as far as grounding on open goes, but apparently it was grounding the buzzer, which doesn't exist.

What I think I might do is add a toggle switch between the door switch and the ground wire of the under-dash light. That way, if I want, I can leave the door open and have the light off or on, at my whim.

Regardless, thank you so much, this is the answer I was looking for, as nothing seemed to work the way I THOUGHT it worked!

[ray_mcavoy]

Originally Posted by blindbug

What I think I might do is add a toggle switch between the door switch and the ground wire of the under-dash light. That way, if I want, I can leave the door open and have the light off or on, at my whim.

Regardless, thank you so much, this is the answer I was looking for, as nothing seemed to work the way I THOUGHT it worked!

You're welcome! Yeah, having an override switch so you can leave the door open without the light being on can be handy at times.