Glove box light - why 3 wires?

[Scott W]

I am installing gauges in my glove box and was hoping to have the new gauge lights come on when I opened the glove box (with the glove box light). There are 3 wires going to the glove box light/switch. 2 yellow and 1 black. Does anyone know how this switch works? why is there 2 yellow. I am used to the typical switch which has one power line going to it and one ground. Does anyone know what wire(s) I would need to tap into? the aftermarket gauges have simple ground and power connections.

 

[Repostyle]

I've never messed with my gb light, but I would assume one goes to the switch to activate the light when you open the door? The other two would be power and ground.

 

[ID89GT]

The switch is built into the light assembly

 

[Scott W]

any idea of how to 'tap' into these wires.

If I clip one of the yellow wires, install the red wire from the aftermarket gauge to one end of the clipped wire, and run the black wire from the gauge to the other the gauge lights would be run in series and shouldn't operate until the glove box switch activates and completes the circuit. I think this will work but I need to get out and test it.

 

[ID89GT]

Are you just looking for a power source for the back lighting? Or is it an electric gauge?

 

[HISSIN50]

Don't cut any wires. Splice into the OEM wire if you need to. You put a test light on each wire and see which one turns the test light on and off when the glove-box button is at rest.

You can daisy-chain your grounds if you like. Same for the lighting power. Keep all the ground wires together and all of the red wires together though (don't literally wire the lighting up in-series, a la red to black to red).

 

[Saleen0679]

There are 3 wires going to the glove box light/switch. 2 yellow and 1 black. Does anyone know how this switch works? why is there 2 yellow.

The 'extra' wire goes off to power other things not associated with the glove box light.

 

[Scott W]

thanks guys. I was able to split the black wire and run one end to the black wires on the aftermarket gauges, and the other end to the red wires. Now the guage lights come on with the glove box light.