1986 C10 No Lowbeams - Highbeams OK

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CATXTraveler

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Dallas
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Matt
Truck Year
1986
Truck Model
C10
Engine Size
350
I have a 1986 C10
Everything worked perfect (although no left indicator- but maybe that’s a separate issue)

Went to pull out the dimmer switch and no low beams. Clicked on high beams and all four headlights turn on.

I am getting power to the red wire to the dimmer switch and the yellow wire is getting power as well.

What should I be looking for next- I don’t want to just throw parts at it.

Thanks in advance.
 

Rickf

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1974, 1954 & a 1937
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K20
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I have a 1986 C10
Everything worked perfect (although no left indicator- but maybe that’s a separate issue)

Went to pull out the dimmer switch and no low beams. Clicked on high beams and all four headlights turn on.

I am getting power to the red wire to the dimmer switch and the yellow wire is getting power as well.

What should I be looking for next- I don’t want to just throw parts at it.

Thanks in advance.

I am confused, Everything worked, then you pulled the switch? Why?

Are you getting power at the low beam bulb? Unlikely but possible that both burnt out at the same time.
 

CATXTraveler

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I mean pull out the switch to turn the headlights on.
Which wire color would have power for the low beams?
 

CATXTraveler

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It does not appear I'm getting any power to the low beam lights. Only when the highbeams are turned on. Would this be indicative of a bad dimmer switch?
 

CATXTraveler

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1986
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C10
Engine Size
350
Got the new headlight switch in, and it doesn't seem to have done the trick.

I was able to figure out the blinker issue so that's resolved.

For the headlights, there is no power going to the tan wire. When I click on the highbeams, the green wire is illuminating.

I tried tracing the tan wire back into the cab, but I can't work out where it's coming from to get to the headlights.

Could anyone help better describe the path of the tan headlight wire so I can keep trying to see where the disconnect is? Does it run all the way up the column to the highbeam selector/ turn indicator switch?
 

CATXTraveler

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1986
Truck Model
C10
Engine Size
350
For anyone with the same problem- it was the high beam/low beam switch located on the steering column (what they call a dimmer switch not to be confused like I was with the switch that actually dims the gauges). Will be ordering a new one.

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