Door controlled courtesy light.

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bigcountry78

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I’m kicking around the idea of adding door switch controlled courtesy lights in my truck. Right now it just has the one floorboard light that is controlled by the headlight switch. The knockouts are there for the door switch, but what is the best way to hook it up? I know I can get the switch at the parts store but what wires do I tap into? Is the factory wire already there? 78 custom deluxe. 0 factory options.
 

MikeB

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Even if your truck does not have interior lamps, your fuse panel may have a fuse labeled "courtesy", "dome" or something like that. If not, find a fused circuit that has a "constant" 12 volt fused source, such as the horn circuit.

Typically, one side of the lamp(s) is wired directly to a 12 volt source. The other is wired to the switch. When the door opens, the switch is grounded, completing the circuit and turning on the lamp. That said, some aftermarket switches may not work that way.

A friend of mine just bought a kit similar to this one for a 30s Chevy sedan he's building. The switches supply a ground to the circuit when the doors are open, as described above.
https://www.summitracing.com/parts/prf-30702
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PrairieDrifter

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As said above. I replaced my fronts, and added a set in the rear doors in my suburban as well.
 

bigcountry78

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Well dang that’s easy enough. I was going to try to rig something with my current setup, but for that price I might as well just go that route. Thank you for that link.
 

75gmck25

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Just remember that they work the opposite of most accessories. The courtesy lights always have 12 volts on one terminal, and the door switch grounds them to complete the circuit and turn them on. This means that any lights you add must have a plastic body, insulation washers, or some other way to keep the light assembly from connecting to ground.

Bruce
 

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Just remember that they work the opposite of most accessories. The courtesy lights always have 12 volts on one terminal, and the door switch grounds them to complete the circuit and turn them on. This means that any lights you add must have a plastic body, insulation washers, or some other way to keep the light assembly from connecting to ground.

Bruce
just replace my door jam switch and yes your right ground controled! :)
 

bigcountry78

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Just remember that they work the opposite of most accessories. The courtesy lights always have 12 volts on one terminal, and the door switch grounds them to complete the circuit and turn them on. This means that any lights you add must have a plastic body, insulation washers, or some other way to keep the light assembly from connecting to ground.

Bruce
Thanks for that, I never would have guessed. I figured they worked just like most other lights.
 

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