My brake lights and taillights aren’t working

Question:

I just got my ’63 Chevy Impala convertible back from the shop after having the power steering pump and pulley replaced. While driving it a couple of days ago someone pulled up beside me and told me my brake lights were not working. When I got home I discovered my taillights also were not working.

I checked the fuse, which looked OK but replaced it anyway. The brake switch above the pedal seemed to be operating OK. I’m looking for a guide to follow to fix both problems. My directionals work fine. Can you help me?

Answer:

To check your Chevy’s electrical circuitry you should have a wiring diagram (preferably in color). A shop manual for your car will have one. You will also need a continuity tester. You can make one out of a simple automotive light bulb (see illustration nearby) or better yet a multi-meter. If the fuses are good and the brake switch works, that most likely means a loose or corroded contact or connection somewhere.

You will need to have a friend help you by turning lights on and off when needed, and to depress the brake pedal for testing. Use the continuity light you fashioned or your multi-meter to make sure your brake light switch is transmitting current to the rear when the brake pedal is depressed. You should also disconnect the battery at the ground, unscrew the light switch from the front of the dash, pull it down gently, and check that its connections are clean and bright and that the small fuse at the front of it is still good.

It could possibly be a grounding problem, but that is not likely because two separate circuits are involved. Each tail light/brake light bulb has two filaments and two wires going to it but uses a common ground through the base of the bulb.

Start at the back of the car and check the bulbs. Filaments can be burned, and contacts corroded to the point where they no longer function. Replace any bulbs that are burned out. And then check each socket for corrosion and poor contact. If the contacts aren’t clean and bright, scrape them lightly with a pocketknife.

Get under the car and trace the taillight/brake light wiring back through the car along the frame to see if there are any breaks or burned spots. When you come to plug-in connections, pull the connections apart and make sure they is not corroded or damaged, and that the contacts inside are clean.