No brake lights or rear drivers turn signal

[KL]

I have been chasing down and cleaning up some minor electrical bugs on my 73 bronco. All marker lights are working. Headlights and tag lights work. Front turn signals both work (drivers side you have to apply pressure on signal lever). Tail lights both burn when headlights are on. Problem is neither brake light works and the left rear turn doesn't work. I know there is power to rear brake lights because I removed the rear housings and when they are at different stages of being screwed back in and grounded they will burn. By the way all have new bulbs. I have also seen the left rear flash but not when everything is back together. Any suggestions?

 

[68rustbucket]

I just went through this myself. Get a test light, and start at the steering column plug. Check the yellow/black wire. I found the connection bad at column plug, cut it out and respliced. You can also check the plug under hood where rear harness plugs into main harness on drivers side. Also check rear harness plug under body at driver rear. Same yellow/black wire at all 3 locations.

 

[Broncobowsher]

Are you running LED bulbs? If so try regular bulbs. I've seen issues with the LEDs

 

[Slowleak]

Try your hazards. If the rears flash then you know the wiring from the dash to the rear is good. Could be your turn switch in the column.

 

[Steve83]

...when they are at different stages of being screwed back in and grounded they will burn.

Then they're NOT grounded when they're fully installed, and that's the problem. Remove them, and clean enough metal to create a ground path. Apply ELECTRICAL grease (not dielectric, or thermal, or chassis grease) to the bare metal to keep it from rusting.