My headlights on my 99 wont turn off. The brights stay on all the time even when the light switch is toggled off and the truck is off. any ideas whats going on?

 

My friends headlight wiring harness burnt up and it caused his lights to not turn off

 

Try unplugging fuse,relay,headlight switch to narrow it down Awiring diagram is very helpful

 

1aMatt is Right, the 7 pin under the back bumper is known to melt down and cause all kinds of problems. seems to be more prevelant on the plowtrucks. mine has done it twice.

unhook it and see if thats the problem. other than that try pulling the headlight relay. to see if its just stuck.

good luck

 

My girlfriend's jeeps windshield supers wouldn't shut off unless we pulled the fuse, then its fusebox caught fire later that night. Still at the dealership waiting for a backordered wiring harness. Electrical problems can be a nightmare, good luck and don't wait too long to tear into it. I'd also suggest everyone invest in fire extinguishers if you haven't already.

 

I had the same trailer plug issue, it made the reverse lights come on.

 

I don't see the trailer plug having anything to do with headlights, if we were talking about parking lights maybe. I would suspect headlight switch or dimmer switch.

 

Where is the head light relay? My truck is doing this too

 

In the fuse box under the hood.