Brake lightdont work
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Teching In
Joined: Oct 2011
Posts: 35
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From: Ft Rucker, Alabama
Brake lightdont work Can anybody please help, i have a 95 T/A. My turn signals and my running lights all work except for my brake lights. the only one that works is the spoiler brake light. Ive repalced the stop swich and the bulbs, but still nothing. any ideas? Thanks.
There's one wire that carries the brake signal to the lights. You should start by checking its voltage at the rear light harness connector. If you peel back the liner in the trunk, you should see the harness. The connector is around 12" inside of where the wires exit the car body.
Worse case scenario, if you can't find the wire causing your problem (its should be in the area described above) you could "jumper" off the positve lead of the 3rd brake light and run it back down to the appropriate wire at the lights, I had to do the reverse of that on one of my old hondas because it had a factory spoiler with a 3rd brake light so the internal 3rd wasn't hooked up right and when I removed the spoiler I had to "jumper" back up to the internal 3rd to get it working. AGAIN THIS IS A WORSE CASE SCENARIO, so no one flame me for saying this is a bad way to fix the problem, its simply bypassing the area of wiring having the problem.
Joined: Nov 2003
Posts: 11,328
Likes: 345
From: Jacksonville, FL (originally from Toronto Canada)
I suspect that you have a faulty turn signal switch. You can eliminate the tail light wiring as a problem because the brake lights and the turn signals use the same bulbs and wiring in a Firebird and you said the turn signals work. Also, since the third brake light works, you can eliminate the brake light switch as the problem - all brake lights use the same switch.
Where the brake lights and turn signals diverge is in the turn signal switch in the steering column. It is set up with internal contacts to pass brake light power through to the tail lights for the side that doesn't have turn signals running (or both sides if the signals aren't in use). You can test this at the T/S switch connector at the base of the steering column. The light blue wire should have power when the brake pedal is pressed - this is the input from the brake switch. If the turn signals are off, both the dark green and the yellow wire should also have power when the brake pedal is pressed - these are the right and left output respectively. If you have power on the light blue but not on the dark green or yellow wires then the T/S switch is faulty.
Where the brake lights and turn signals diverge is in the turn signal switch in the steering column. It is set up with internal contacts to pass brake light power through to the tail lights for the side that doesn't have turn signals running (or both sides if the signals aren't in use). You can test this at the T/S switch connector at the base of the steering column. The light blue wire should have power when the brake pedal is pressed - this is the input from the brake switch. If the turn signals are off, both the dark green and the yellow wire should also have power when the brake pedal is pressed - these are the right and left output respectively. If you have power on the light blue but not on the dark green or yellow wires then the T/S switch is faulty.
Joined: Nov 2003
Posts: 11,328
Likes: 345
From: Jacksonville, FL (originally from Toronto Canada)
Worse case scenario, if you can't find the wire causing your problem (its should be in the area described above) you could "jumper" off the positve lead of the 3rd brake light and run it back down to the appropriate wire at the lights, I had to do the reverse of that on one of my old hondas because it had a factory spoiler with a 3rd brake light so the internal 3rd wasn't hooked up right and when I removed the spoiler I had to "jumper" back up to the internal 3rd to get it working. AGAIN THIS IS A WORSE CASE SCENARIO, so no one flame me for saying this is a bad way to fix the problem, its simply bypassing the area of wiring having the problem.
This won't work because the same lights are used for brake and for turn signal. If you patch the lamps into the third brake light, the turn signal wouldn't flash when the brakes are applied because the lights would have constant power from the third brake light. This is the reason that ghetto patching is never a good idea - there are usually unintended consequences.
I suspect that you have a faulty turn signal switch. You can eliminate the tail light wiring as a problem because the brake lights and the turn signals use the same bulbs and wiring in a Firebird and you said the turn signals work. Also, since the third brake light works, you can eliminate the brake light switch as the problem - all brake lights use the same switch.
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Teching In
Joined: May 2009
Posts: 21
Likes: 0
From: college station, tx
Mine is doing this as well, but only on the left side, and it's random at that, (one minute my left brake lights work, the next, they don't)
The yellow wire feeds to the left correct? So is there a way I can tap the yellow wire as it exits the connector for the turn signal switch to see if my problem is with the switch vs. with a possible kink in the wire somewhere down the line towards the taillight?
As a side not I havent been able to determine if the left turn signal is affected, I just know the brake light is. If the turn signal is NOT affected then it would be safe to say the yellow wire is physically fine and the issue is likely with the Turn Signal switch correct?
The yellow wire feeds to the left correct? So is there a way I can tap the yellow wire as it exits the connector for the turn signal switch to see if my problem is with the switch vs. with a possible kink in the wire somewhere down the line towards the taillight?
As a side not I havent been able to determine if the left turn signal is affected, I just know the brake light is. If the turn signal is NOT affected then it would be safe to say the yellow wire is physically fine and the issue is likely with the Turn Signal switch correct?
If the turns always work but the brake randomly does not, then I'd suspect the switch. Could try turning the signal on then off when the brake isn't working on that side to see if it makes it work again. In this case it is definitely not the wiring, bulb, or socket.
If both the turn and the brake randomly stop working at the same time I'd suspect bulb/socket first, then electrical connection next. The actual wire itself is last on the list as there isn't a typical pinch point anywhere like the wiring in the doors for example.
If both the turn and the brake randomly stop working at the same time I'd suspect bulb/socket first, then electrical connection next. The actual wire itself is last on the list as there isn't a typical pinch point anywhere like the wiring in the doors for example.
Teching In
Joined: May 2009
Posts: 21
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From: college station, tx
understandable, the trick is catching it while it's not working, and so far I havent been able to (everytime I get home at night I check my reflection in the car next me) but thank you for the clarification.
