Electrical Problem (Parking Lights & dash lights)

[rusty79beast]

I have run into yet another small problem When you turn the lights on you get the headlights to light up, but not the tailights, front marker lights, or the dash lights. How would one go about finding the fault? My guess would be to somehow check the switch first. Short of swapping in another switch how could you test the switch? Do you just check for voltage when the light switch is pulled out and trace the wires?? Hopefully one thing is at fault here and not more. One more thing is that the brake lights and turn signals work & this is on a 91 K5. Any guidance would be greatly appreciated. You guys rock

 

[tiger9297]

I have run into yet another small problem When you turn the lights on you get the headlights to light up, but not the tailights, front marker lights, or the dash lights. How would one go about finding the fault? My guess would be to somehow check the switch first. Short of swapping in another switch how could you test the switch? Do you just check for voltage when the light switch is pulled out and trace the wires?? Hopefully one thing is at fault here and not more. One more thing is that the brake lights and turn signals work & this is on a 91 K5. Any guidance would be greatly appreciated. You guys rock

Your fuse is probably blown. Mine did that on my '90 K5 and the problem was a short in my trailer light wires.

 

[Jagged]

My headlight switch caused the same problem a couple months ago. I now have a set of "custom" toggle switches for the dome, parking, and headlights.

 

[rusty79beast]

Oh, yeah I forgot to mention that I checked the fuses first, and none are blown. So hopefully it is the switch and I can just replace that and be back in business. If there are any other possibilities please let me know!

Thanks guys

 

[Yukon Jack]

I fixed this exact problem last night on my 69. (almost exact - I didn't have brake lights either) The brake lamp switch that is activated by the brake pedal wasn't getting power. Must have been a problem in the wire from the fuse block to the brake lamp switch. I ran a hot lead from the fuse block into the brake lamp switch and everything fired right up. Took me hours to find the problem Hope this helps you.

 

[Habez]

Mine did that exact same thing. It was a fuse. Might want to double check the fuses. I had suggestions to check the switch too, so might want to check there. You could probably find one in a junk yard for really cheap and swap it in.

 

[boggerless]

check and clean all the grounds at the headlights and turn signals.i had some wires cut at the fuseblock myself.THEN look at the tail lights,the ground there was pulled out on mine cuz of the mud. my main light problem was the harness going into the guage dluster was 3/4 unpluged. if that don't do it look for pinced wires .and don't forget both tail lights need a ground.