My Daughter has a 1997 Cavalier. Recently, her Brake Lights and both rear turn signals went out. The center brake light is working. When you put the car in reverse, both rear bulbs work. Additional Info only: All running lights, headlights, both front turn signals work fine. Hazards only work in the front. Fuses are good and so are the bulbs. Ohmed out the fuses.

Being very solid in electrical, I started digging in. The Rear brake light connectors are two wire into a socket. (The sockets are intermitant and a bad design. I replaced them just for that reason). Measured the voltage at the brake light connector. No voltage seen on either connector with brake pedal pressed. Additionally tested with turn signals on, flashers on, lights on etc... Even used a different ground. All no effect. Oddly, when in reverse, I measure 13V solid across each connector. This implies the rear wiring is solid since it is common and no voltage is being sent to the rear of the vehicle. Sounds like a switch.

Since the break light/turn signal are common, I replace the Turn signal SW inside the steering column. $60. No effect.
Next I replaced the turn signal Flasher above the brake pedal. $17 No effect. Didn't think so since it was clicking.

Replaced the brake pedal sw $9. Ohmed out the old one and it was still fine. High resistance with the plunger depressed and short with it open. I made sure the plunger was adjusted properly and fully open on pressing the pedal. No effect. There is also a second plunger under there as well which I tested with a ohm meter. I also works fine.

So now that I have gone through all the sw components and they are working fine, were is the best likely place to look. Is there a known problem with wiring under the dash.

I would have thought the Turn Signal multifunction sw would have fixed this but it didn't. I also put a second one in hoping the first one was defective. it wasn't.

Any idea's out there. I am going to test the voltage at the pedal tonight however not looking forward to it. Not easy to get at it on your back at my age.

Fustrated but determined.
Greg

 

My suggestion, pull the wire from the brake switch wire off the switch, jump it to 12 volts, if they come on, problem is up stream of the switch, if no, then it is something downstream. You stated you ohmed the switch out, did you check for power?