no high beams

[hayseed71]

The other night i went to turn on my high beams and the headlights went out. I figured it was the dimmer switch so I just replaced it. Could it possibly be the headlight switch? Low beams work as does the panel dimmer and dome light. It just seems a little unlikely that both high beams would burn out at exactly the same time.

[chevy_mike]

If you replaced the floor switch, verify that you have power going to the headlight high beam wires. Could be a broken wire, loose connector. Headlight switch does nothing in regards to the high/low beams, it just gives power to the floor switch and the wiring to the headlights.

[hayseed71]

I did some more checking and both high beams are blown. Tested the dimmer switch and when on high it has a short to ground. So the switch blew both bulbs. I didnt think the beadlight switch had anything to do with high or low. Thanks for the input.

[Brad54]

I hate electrical gremlins...
I had the contacts come out of the Bakelight headlight switch housing, and they bounced around inside the housing, eventually crossing the wrong thing and shorting wires.
The result was some of the wires going to the dimmer burned up, as well as other wires under the dash.
I had headlights, no tail lights, intermittent brights, and the turn signals and brake lights worked.

Oh, and I discovered that in the rain, in the fall, a burning wiring harness smells just like the burning leaf piles people put in the ditch next to the road.

-Brad

[hayseed71]

Yeah this truck has a few gremlins. At some point in time i will probably rewire the whole thing. Right now the left turn signal blinks a little faster than once per second and the right blinks about once every 1.5 seconds. Has to be some excess resistance somewhere. Ahhh the joys of buying an old truck.

[Backpayne]

Same thing happened to me; both high beams went out at the same time. I checked everything else before I checked the actual lights.

[hayseed71]

Sometimes I forget to use the K.I.S.S. principle.

[jayoldschool]

Lights are on my "to-do" list in the Spring. The parking lights work, the headlights... no. I had to hurry home a couple times as the days got shorter last Fall!

[hayseed71]

Originally Posted by jayoldschool

Lights are on my "to-do" list in the Spring. The parking lights work, the headlights... no. I had to hurry home a couple times as the days got shorter last Fall!

That could turn into a bad situation. You could always run a temporary setup through a toggle switch and relay. That way you wouldnt have to worry about being caught in the dark.

[sanford66]

Check out the wiring connector plug at the dimmer switch on the floor. These are notorious for going bad. Mine did the same thing and I found the plug had worn through against the floor board and was shorted to ground. I could jiggle the wires and get the high beams to work off and on. You will have to find a good used plug off another truck because these aren't being reproduced. I went through 6 of my parts trucks before I found a good one. Joseph

[TJ's Chevy]

It was a ground issue when I had that problem.

[rrbaker15]

My son and I just purchased a 1972 GMC C15, headlights were working and somehow the high beam were turned on as we could not figure where that switch is, is the switch the same for GMC as it's for Chevy?

Update: the previous owner had the floor switch hidden behind the rug, not sure why but we discovered that the dimmer switch is giving us flimsy results so will investigate to see if we need to replace or other not.