Headlight issues

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Catfish26kc

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Hey guys, my first post . I'm having issues with headlights randomly going on and off on my 86 gmc. I replaced the dimmer switch 3 times. I now have an orange wire at the plug that is warm to the touch and have only the top headlights working but all 4 come on when I click the high beams on. Is this supposed to happen?
 

Catfish26kc

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I changed the dimmer its fine, changed the headlight switch 3 times. It's the 2 orange wires from the headlight switch that are kinda hot . The dimmer is fine and works well... had to edit my first post. Ugh!
 

Turbo4whl

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From the issue you describe, the most common cause is the headlight wire has rubbed through and has a short to ground.

Yes, the upper headlights have two filaments inside. They are on for the low beams. Then all four lights are on for the high beams.

The headlights do not have a fuse. There is a thermal breaker that trips when too much current passes. So a wire that sometimes shorts to ground will trip the thermal breaker. When it cools, the breaker resets and the lights will work again.

Check the wires to the dimmer switch, they can rub through. Pull the headlights and check their wires, another place where they can sometimes fail.
 

Catfish26kc

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Stock headlights.... yes
 

RustyPile

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Those orange wires have nothing to do with the headlights.. One of those orange wires comes from the fuse box, providing power for tail lights, and dome/courtesy lights. The other one goes to the courtesy lights.. The orange wires should have voltage on them all the time, not switched. The power for the tail lights goes through this wire to the headlight switch and when turned on, goes on to the tail lights.. There's no reason for those orange wires to get hot as they are protected by the fuse.. Check the tail light fuse and be sure it is the correct value. Nothing else should be connected to this wire (additional lights, accessories, etc.) as it's not gauged for additional current.
 

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