My taillights won't come on
There is usually a brake light switch. It may be attached just behind the brake pedal's arm, or located on the master cylinder.
How do I get to the switch
Is it tail light or brake lights or both? If the Brake light switch is under the dash attached behind the brake pedal arm it is a difficult reach. You have to lay on your back in the floor, probably with legs out the door. On my 77 Astre, I had to remove the dash underpinning to get at it. From there you just unplug the wires (there may be retaining clips on the sides that have to be pushed out to release), screw out the old switch. Then just reverse the steps to install the new one. If it is on the Master Cylinder it is much easier. There will be a switch with wire attached, but look for the one under the dash with a flashlight first. But if no lights at all work to the rear, that may be a different problem. If the headlights work, but not the tail lights the multi function light switch is probably OK. In that case you may have a wire short or a bad socket. There are contact nubs in the socket that must be clean in order to make contact.You may be able to find a video on you tube on the internet that will show a person doing the actual job of "changing a brake light switch", if it is only the brake lights. Best of luck! Auto electric can be quite involved, hope yours is an easy fix.
Looking for a Used Grand Prix in your area?
CarGurus has 3,713 nationwide Grand Prix listings starting at $1,100.
Search Pontiac Grand Prix Questions
Pontiac Grand Prix Experts