stupid brake lights - help!
Thread Starter
Teching In
Joined: Oct 2006
Posts: 2
Likes: 0
From: DE
stupid brake lights - help! My driver's side brake light only illuminates if the headlight/parking lights are off. Now, on my '97 Z28, the brake light bulb is a dual filament bulb. When the headlights/parking lights are turned on (and the brake light bulb lights dimmly - 1 filament) and I press the brake, the bulb goes completely out until you let off the brake. Passenger side works fine. I've double checked my ground, replaced the bulb, and made sure the bulb is in the right way. I've cleaned out the bulb holder with battery terminal cleaner and a wire brush, but no good. I wonder if I should just replace the bulb holder 
Any help would be greatly appreciated...
Any help would be greatly appreciated...
Joined: Nov 2003
Posts: 11,328
Likes: 346
From: Jacksonville, FL (originally from Toronto Canada)
You've done all the right things so far. Rather than guessing and replacing parts, it's now time to get out the test light or multimeter. Remove the bulb from the socket and test for a good ground and power. This is easy to do if you have 1157 bulbs (the round bayonet type) rather than the newer 3157 wedge bulbs - I'm not sure which type is in a 97. If you have 1157 bulbs then ground will be on the entire outside metal sleeve of the socket and the two pins at the bottom of the socket will carry power for taillights and brake lights respectively. With the wedge bulbs it is probably easier to use a test light with a sharp probe on the wires at the backside of the socket - ground is black, taillight is brown, and brake light is either green or yellow depending on which side of the car you're checking. If everything checks out then it's either the bulb or a problem with the socket (pins misaligned or something). If something doesn't test the way it should then you can trace that circuit to find the break.
