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Yes of course. Just follow the black wire leading away from the bulbs. It should bolt to the chassis somewhere.
I seem to recall there are 2, one for each side of the vehicle.
AFAIK however, there's not a discrete one that serves only the brake lights; especially not in a Firebird, where the same bulbs are the brake lights AND the turn signals. If the TS work but the brake lights don't, then the problem CANNOT be the bulbs, grounds, or the wiring from the steering column onward. More likely, if a ground is disconnected, one whole side won't work, or it'll work but be real weird.
In a Firebird, since the same bulbs perform both functions, the power flow goes from the brake/hazard fuse, to the brake light switch, into the steering column to the TS switch, back out of the steering column, to the Fisher Body harness, to the bulbs. The brake and TS share EVERYTHING from the TS switch onwards.
You're likely to have more success with a test light. Check starting at the fuse first, then at the brake light switch for 12V when you press the pedal.
Hmmmm ok. So essentially the problem does not lie within the circuit that leads from the tail light fuse or the turn signal switch but specifically through the wiring for the brake light switch. I used a test light and it was showing power going in through the orange wire, then when I released the switch (simulating the brake pedal being pushed) both light blue wires for the turn signal switch and brake lights showed power through them. I'll get a multimeter and test for 12v later today. If I find 12v at the switch what would be the next step? Just tracing the brake light wire?
If 12V is coming out of the BL sw, then the problem is the hazard/TS sw in the steering column.
THIMK: you have a single bulb, or group of bulbs all wired together as though 1 big bulb, that each have 2 filaments; the lower intensity one for the taillights, and the high intensity one that does TS, BL, & haz. BOTH filaments use THE SAME ground. Therefore if ANY light function works, the ground for the bulbs THAT WORK are OK.
From there, THIMK about what the switch operation and logic must be.
There are 3 sources of 12V that go into the steering column to get to the haz/TS sw and then onward toward the bulbs; connected to pins L, K, & P of the column connector as you can see on the schematic. 1 comes from the haz flasher, 1 comes from the TS flasher, and 1 comes from the BL sw. If the haz & TL are both OFF, then the bulbs will get power from the BL sw. If the haz are OFF and 1 of the TS is ON, then the bulb ON THAT SIDE ONLY gets disconnected from the BL sw, and instead gets connected to the TS flasher. If the haz are ON, then BOTH bulbs are disconnected from BOTH the TS and BL sources, and connected to the haz flasher.
THIMK: Here's your logic tree then.
_
If the hazards work normally, then the hazard/brake fuse is good, and ALL of the wiring downstream of that switch, and the bulbs, and the ground side of the wiring, is ALL working correctly.
If the TS ALSO work normally, then the haz switchover function in the haz/TS sw is working properly.
At this point, if the BL DO NOT work, the problem HAS TO BE the part of the haz/TS sw that disconnects the bulbs from the BL source and connects them to the TS source. Specifically, the part of the sw that is active when the TSs are both OFF.
Logic. Doesn't even require a test light, let alone any detailed electrical knowledge; just look at the car, watch what it does, and use LOGIC.
Do the hazards work correctly? Do the TSs work correctly?
If 12V is coming out of the BL sw, then the problem is the hazard/TS sw in the steering column.
THIMK: you have a single bulb, or group of bulbs all wired together as though 1 big bulb, that each have 2 filaments; the lower intensity one for the taillights, and the high intensity one that does TS, BL, & haz. BOTH filaments use THE SAME ground. Therefore if ANY light function works, the ground for the bulbs THAT WORK are OK.
From there, THIMK about what the switch operation and logic must be.
There are 3 sources of 12V that go into the steering column to get to the haz/TS sw and then onward toward the bulbs; connected to pins L, K, & P of the column connector as you can see on the schematic. 1 comes from the haz flasher, 1 comes from the TS flasher, and 1 comes from the BL sw. If the haz & TL are both OFF, then the bulbs will get power from the BL sw. If the haz are OFF and 1 of the TS is ON, then the bulb ON THAT SIDE ONLY gets disconnected from the BL sw, and instead gets connected to the TS flasher. If the haz are ON, then BOTH bulbs are disconnected from BOTH the TS and BL sources, and connected to the haz flasher.
THIMK: Here's your logic tree then.
_
If the hazards work normally, then the hazard/brake fuse is good, and ALL of the wiring downstream of that switch, and the bulbs, and the ground side of the wiring, is ALL working correctly.
If the TS ALSO work normally, then the haz switchover function in the haz/TS sw is working properly.
At this point, if the BL DO NOT work, the problem HAS TO BE the part of the haz/TS sw that disconnects the bulbs from the BL source and connects them to the TS source. Specifically, the part of the sw that is active when the TSs are both OFF.
Logic. Doesn't even require a test light, let alone any detailed electrical knowledge; just look at the car, watch what it does, and use LOGIC.
Do the hazards work correctly? Do the TSs work correctly?
This was very helpful. Both the TS and hazards work so would you just recommend replacing the turn signal switch? When I looked under my dash yesterday I saw a connector that looks similar to the one which I am seeing when I look on the autozone website for the turn signal switch, specifically the colors on the connector. I remember yesterday a white wire at the end before the blue one being loose so I will inspect it (or even just order another).
Went to go mess around with the white wire and the pin just snapped right off the wire. Already have a new turn signal switch to put in so hopefully can get that done soon and we'll see.
Yes, unless the wire that's efffed up is the brake light one. I don't have a Firebird manual to look up the color codes to be sure.
Yes also, that is the TS sw connector. The wires you can see in the photo go up through the column and are permanently made onto, and therefore part of, that switch. If they're messed up, just change the switch. When you do that, attach a string or dental floss or something to the old one before you pull it out, and use that to pull the new one down the column.
Yes, unless the wire that's efffed up is the brake light one. I don't have a Firebird manual to look up the color codes to be sure.
Yes also, that is the TS sw connector. The wires you can see in the photo go up through the column and are permanently made onto, and therefore part of, that switch. If they're messed up, just change the switch. When you do that, attach a string or dental floss or something to the old one before you pull it out, and use that to pull the new one down the column.
I'm very much hoping this is the issue. Regardless, this connector needs to be replaced as some of the other pins are moving as well and the white wire (which I believe links to the brake light switch) does not have a pin anymore. Fingers crossed!
Yes, unless the wire that's efffed up is the brake light one. I don't have a Firebird manual to look up the color codes to be sure.
Yes also, that is the TS sw connector. The wires you can see in the photo go up through the column and are permanently made onto, and therefore part of, that switch. If they're messed up, just change the switch. When you do that, attach a string or dental floss or something to the old one before you pull it out, and use that to pull the new one down the column.
Just wanted to say thank you for your advice. Just got done putting in the new turn signal switch and voila! My brake lights work again! I would have definitely overlooked this if it was not for you so I greatly appreciate your advice.
10-16-2020, 06:06 PM
