Tail lights cutting off

[brianstrange]

I have a 77 harness in my Bronco. Before re-assembly, I went over the whole thing (unwrapped) and there were no signs of any issues.

Last night, my wife followed me home, and the tail lights went out for about 5-10 seconds. She was unsure about the brake lights, and I'm unsure about the front markers. The headlights did not go out on my, and I have them on a relay circuit that triggered by the headlight switch. Last year, my dash lights went out for a few seconds, came on after fiddling with the switch.


Has anyone had a Headlight switch fail like this for the taillight or marker light sections?

 

[Rustytruck]

Check the ground on the drivers side frame rail by the rear bumper. There is also the grounding issue through the tail light buckets themselves where the assembly is riveted together.

 

[brianstrange]

I've already ruled this out. Each bucket and the license plate light has it's own ground. All are clean and good to go. All three went out at the same time, so it's telling me a broken wire or switch issue.

Check the ground on the drivers side frame rail by the rear bumper. There is also the grounding issue through the tail light buckets themselves where the assembly is riveted together.

 

[SHX669]

Is your Bronco Recently painted ? I know several who have had issues after a nice paint job . It sometimes will insulate /seal the frame from the connector being " grounded ".
What I'm getting at is I believe the tail light bucket has to be grounded to the body also . Have you checked that ? - Oh and the body to the battery and the frame to the body .

 

[Steve83]

Each bucket and the license plate light has it's own ground.

Going to where, exactly?

Start at the battery terminals. Click this & read all the captions:



Then check the starter relay terminals, and the block ground, and the body ground (if there IS one):

.

If you can't find a body or frame ground, add some.

 

[brianstrange]

To the frame. No other electronics have an issue, so at this point, I'm looking for info on failing headlight switches, but only on the park lamp circuit.



All system and component grounds are bolted stud assemblies with a service fastener (nut.) They are all good. This is why I'm asking the question about the switch.

Going to where, exactly?

Start at the battery terminals. Click this & read all the captions:



Then check the starter relay terminals, and the block ground, and the body ground (if there IS one):

.

If you can't find a body or frame ground, add some.

 

[tasker]

GET THIS fixed before mine is done!;D