Brake light sometimes works
Thread Starter
|
Freshman User
Joined: Jul 1999
Posts: 28
Likes: 0
Brake light sometimes works
The pass. side brake lamp only turns on when the left turn signal is on. It works fine with the right turn signal and headlights. When no turn signal is set, the only brake light is the driver's side light. All other lights on the truck are fine.
I checked with a voltage meter at the wiring harness (and wires a few inches before that) that comes out of the cab and have seen the same problem up there, so the problem isn't with the wires between the bulb and the engine compartment. Also, the truck is a 1970 F-100 and the wire that powers the pass. side brake light is green (in case it helps any)
I have no idea what could be causing this - the fact that the pass. side brake light only works when one of the turn signals is set seems strange. Any help is greatly appreciated.
I checked with a voltage meter at the wiring harness (and wires a few inches before that) that comes out of the cab and have seen the same problem up there, so the problem isn't with the wires between the bulb and the engine compartment. Also, the truck is a 1970 F-100 and the wire that powers the pass. side brake light is green (in case it helps any)
I have no idea what could be causing this - the fact that the pass. side brake light only works when one of the turn signals is set seems strange. Any help is greatly appreciated.
Guest
Posts: n/a
Brake light sometimes works
Brandon,
I would suspect the turnsignal switch is the problem. Your brake light switch feeds power to the turnsignal switch. When the switch is in the neutral postion both brake lights are connected. The switch then disconnects the brake light on the side in which the switch is moved and keeps the opposite side connected to the brake light switch.
So check the wires at the turnsignal switch plug.
You can also move the handle up and down in the neutral position and see if the light comes on if it does the turnsignal switch is the problem.
Good luck!
I would suspect the turnsignal switch is the problem. Your brake light switch feeds power to the turnsignal switch. When the switch is in the neutral postion both brake lights are connected. The switch then disconnects the brake light on the side in which the switch is moved and keeps the opposite side connected to the brake light switch.
So check the wires at the turnsignal switch plug.
You can also move the handle up and down in the neutral position and see if the light comes on if it does the turnsignal switch is the problem.
Good luck!
Fleet Owner
Joined: Jun 1999
Posts: 24,552
Likes: 74
From: Creedmoor, North Carolina
Brake light sometimes works
Brandon, I can relate to your problem. The left brake light stopped working on one of my trucks. The tail light would burn, and the signal light would burn, but not the brake.
Since there are only two wires to the bulb, and one of those (is a common for both tails) then the problem is in the other wire.
I unpluged the connection, pulled, spit, and scratched, put the darn thing back together and it now works. I don't have a clue what was wrong.
Since there are only two wires to the bulb, and one of those (is a common for both tails) then the problem is in the other wire.
I unpluged the connection, pulled, spit, and scratched, put the darn thing back together and it now works. I don't have a clue what was wrong.
