Today when I got to work I noticed my headlights still on 10 minutes after getting out of my truck. It's 02 gmc Sierra 2500. So the headlights will not go off, the switch is on off, and I tried pushing the override button multiple times still not doing anything, tried switching from dim to brights, still won't go off, tried changing the headlamp relay, still on, and tried changing the headlight switch, still on. Tried to disconnect the negative battery cables for 30 minutes, still on. I don't have keyless entry but when I put my key in the door to unlock the truck, when I turn it to unlock, they go off. But when I turn it back to where I can pull the key out they come back on... Anyone?? Also throughout all of this the dash lights do not come on with headlights unless its dark so I think that eliminates the little sensor on the dash..
Headlights won't go off!!
- Thread starter BrystonLb7
- Start date
I'd start by taking the dash bezel off, pull the switch and unplug it
If that works it's probably just the switch!
If that works it's probably just the switch!
The lights still stay on even with the relay and headlight switch pulled and disconnected? The headlight switch and the BCM control the headlight relay. If unplugging the switch doesn't change it then I would look into the BCM or the wiring between the BCM and relay. If the lights stay on even with the relay pulled you have a hard positive short somewhere between the fuse block and the light bulbs.
Attached is the whole headlight schematic for your 2002.
If the headlights stay on with the relay removed (are you removing the correct relay??) then there is a short from +12V to the headlight wiring.
If the headlights stay on with the dimmer switch unplugged (this is NOT the "auto/park/headlight" on/off switch, which comes before the relay), then there is a short to ground in the headlight wiring.
If both happen, you have lots of shorts! Check the harness for rat/squirrel damage.
If the headlights stay on with the relay removed (are you removing the correct relay??) then there is a short from +12V to the headlight wiring.
If the headlights stay on with the dimmer switch unplugged (this is NOT the "auto/park/headlight" on/off switch, which comes before the relay), then there is a short to ground in the headlight wiring.
If both happen, you have lots of shorts! Check the harness for rat/squirrel damage.
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The headlights turn off if I pull the relay out. What's got me confused is when I put the key in the door when I turn it to unlock they go off, but when I turn it back to pull it out they come back on
Sounds like a body control module problem. Or there is some damaged wiring on that side of things.
I would disconnect the BCM and see if the headlights work manually (with the switch) at that point.
I would disconnect the BCM and see if the headlights work manually (with the switch) at that point.