Headlights go on and off

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rusted nuts

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I would start putting things back the way they they should be 1st.
 

gmbellew

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actually the only "old" part is the switch. with integral circuit breaker. I'd consider replacing it to see if that is it. or add relays to reduce load on the switch and see if that helps. do the highs and lows both do it?
 

82sbshortbed

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Yes both high and low do it.
 

82sbshortbed

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Also I have these lose wires coming out of the harness. The two yellow or maybe orange wires on drivers side the single one on passenger side. Anyone know what they go too?

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82sbshortbed

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Thought one on passenger side might be horn. I ran my own horn with button on dash because I couldn't get it to work. Po put aftermarket steering wheel on too. Lol
 

Ellie Niner

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The way your headlights are going out, then coming back on looks exactly like an overloaded circuit breaker (and not a dead short). If you're running the stock bulbs those new headlights came with (they should be a 9006 in the low beam and 9005 in the high), they're well under the 15 amp rating of the circuit breaker inside the headlight switch. Thermal breakers almost start tripping at less than their rated amperage as they fail, so it's pretty likely... You could unplug one headlight and see if the other stays lit to test the theory. Do you know what that relay mounted to the header panel in your last photo is feeding?

Your dash lights, dope light, and courtesy light are on three different circuits that are unrelated to the headlight circuit. I'd just focus on the headlights, then start tackling the other stuff.
 

Grit dog

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It’s not the alternator.
Alt could be disconnected and the lights will burn until the battery is dead.
Hard to say with the “work” that’s been done in the past but a headlight switch is like $20 and half a beer job.
 

Grit dog

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Also NEVER EVER.... have I asked anyone to "hold my Beer"..........NEVER!!!.....lol......too many bad things could happen?
Man, you probably coined the term before it was actually a saying, over there in Idahoo! I’ve seen some of the old pics you’ve posted! Lol
Cheers!
 

82sbshortbed

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This truck doesn't happen to have an aftermarket relay kit on it for the headlights does it?
Yes it does but they were doing this before I pit it on. It allows all four to come on on high beams.
 

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