Headlight turn on without turning on light switch

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delkaandrew

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Hello all, a little back story.
I was in a four car pileup a year ago and decided to rebuild the whole front end of my truck. When putting it all together and plugging in all the wires to the headlights back in I noticed that when I turn the key to acc power the low beams turn on without needing to turn the headlight switch. It didn’t use to do that prior to the rebuild. Is it possible the switch has gone bad? I’ve already tried unplugging and reinstalling the connectors and putting dielectric grease on. Am I missing something or has anyone else had this issue?
 

RichLo

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DRL's were turned off before then something reset during your repair to engage them again...

 

GoToGuy

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It's not a computer, turning it off and on to clear memory.
Your missing the diagnostic activity. Did you do any wiring repairs? Did you change anything, as in change from factory stock wiring circuits?
If you unplug the headlight switch , turn key switch to run, not start position, to run are headlights on? 1)Yes then check headlight wiring for short to power headlights.
2) if not, start with headlight switch testing.
Without more info you may have to do a wire trace to find crossed short.
 

HotWheelsBurban

Gotta have 4 doors..... Rawhide, TOTY 2023!
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Both my trucks have DRLs but they only work consistently on the crew cab. Both of my Burbs had/have issues with the DRL box working intermittently. They'll be on for several months, then quit with no warning, then repeat the process. I changed the box on the other Burb, but I'm not flexible enough anymore to crawl under the dashboard and stand on my head, to get to it on the current Burb.
 

delkaandrew

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It's not a computer, turning it off and on to clear memory.
Your missing the diagnostic activity. Did you do any wiring repairs? Did you change anything, as in change from factory stock wiring circuits?
If you unplug the headlight switch , turn key switch to run, not start position, to run are headlights on? 1)Yes then check headlight wiring for short to power headlights.
2) if not, start with headlight switch testing.
Without more info you may have to do a wire trace to find crossed short.
I did no wiring repairs, simply unplugged the harness and plugged it back in when I was done
 
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