Thread: 3rd Brake light INOP.

1997 Grand Prix GT 4 door.

3rd brake light (high mount) (the one in the rear window) does not work. Bulbs good, connections good, not getting power. Is there a connection somewhere I should be looking at, downstream in the harness? The left and right brake lights work, running lights work, just no 3rd brake light.

Any insight would be appreciated.


Jay

Bump? Anyone have a wiring diagram I can work with maybe?

Jay

in my regal there is a harness to the 3 rd light, it plugged in under the rear deck panel on the pass side. looks like it went into the trunk.


edit: you need to remove the whole back seat to get the rear deck off.

Originally Posted by 98GPGT2D

Bump? Anyone have a wiring diagram I can work with maybe?

Jay

...

Thanks Bronco.

My GF has her drivers test on Tuesday, and I have to get the 3rd brake light working for then. I think for now, im going to run a wire from the tail light harness, up to the 3rd, to get her through the drivers test, and will find and properly fix the issue there after. Now, my question is, do you have the tail light harness wiring diagram? I'm looking for the brake light signal wire for either the left or right rear tail light. I would use a test light to find out, but I dont have a 2nd person around right now to press the brake pedal so I can probe the connection in the RR corner.

I think its the brown wire I need to tap into? I already found out that the green and yellow are the signals, from the previous diagram you posted up. Black is ground, so it only makes sense that brown is the brake signal?


Jay

if you tap into the brake wire, and then to the 3 light, that should work. if it dont, you now know its the socket or its ground.