No headlights

[Central4runneR]

So I just bought a 2000 GMC 3/4 ton CC SB old body style and i have no headlights when turned on with the switch. The drl's work so i know the bulbs are good and all the parking lights work. The high beams work with the headlight switch in the on position. im in the process of chasin it down but without a diagram it kinda hard. i have power at the yellow wire on the back of the switch when turned to the headlight position, havent figured out were that wire goes yet and thats were im at now so any help would be appriciated

 

[junkyard jim]

Try the relay

 

[84Toyota4x4]

I assume you have checked while its running? I only mention it because my boss had me install a stereo with navigation, back up camera, had to integrate with the stock steering wheel controls, On Star, etc into his 04 GMC Sierra. After the install while checking out the stereo he freaked out that I had messed up his headlights because they wouldn't turn on and figured I had messed something up while I had the truck torn apart so far. Turns out it was because the engine wasn't running. The DRLs and driving lights came on, but not the headlights (because it has auto headlights). Just some food for thought. It might pay to know if its supposed to have some kind of auto headlight system anyway just in case for trouble shooting purposes.

~T.J.

 

[Central4runneR]

I tried lookin for a relay i didnt see one, may of had a moment of retardation

I have checked it while runnin and the drl's are on but when you turn the headlight switch on the drl's turn off but no headlights (which are the same lights). All the parking lights are on. It dosent have auto headlights its still the old body style. Our 02 yukon has auto headlights but its the next body style and the yukons drl's are seperate from the headlights.

I was doin some searchin somewhere and read somethin about a drl circut board, im also wonderin if it might have somethin to do with the multifunction switch cause the high beams still work. Ill do some more rootin around in it tomorrow

 

[zukkev]

The DRL's are run off the high beam circuit---thru the DRL module (which basically reduces voltage to the high beams, giving the DRLs a dimmer lighting)---have you checked to see if you have power at the headlamps on the lo-beam circuit? could just be two bad bulbs...I have seen this before on more than one occasion...

 

[Central4runneR]

yeah i have checked for power at the lamp just on the driver side, pass side is buried and didnt have time to pull it out gonna do that tomorrow.

Do you know where the drl module is mabye i could trace the power when the headlight switch is on to that im pretty sure its the yellow wire out of the switch. A pain in the ass with no diagram

 

[zukkev]

I don't know where it is offhand...OBS chevs are notorious for failed headlight switches....pop the switch out of the dash, and check closely at the connector for burnt/discolored terminals....

 

[03 CON]

What Kev said, my DRL run off the high beam.....

 

[Central4runneR]

so i went out and found the drl circut board under the dash its in a grey box just to the left of the sterring colum.I pulled the board out to check if anything was burned up, it looked fine so i reinstalled it and for shits and grins i fliped the switch to the headlights on and what ya know they work. We'll see how long they work

Thanks for your guys' input