Classic/Antique Car Repair: No brake lights, turn signal switch, fuse clip

Question
QUESTION: I have a 1964 Chevy Impala that my brake lights stop working.I had almost the same problem about 6 months ago except only one side worked when i applied the brakes.I did replace the turn single assy and everything worked great.By the way everything works tail lights,turn singles except the brake lights. Now both don't work,Can it be that turn single switch again? I did disconect the two wires going to the brake switch and connected them together..nothing...fuses are good.Thank you  Henry

ANSWER: Yes, it can be the turn signal switch again, but since it has recently been fiddled with, before blaming it, I'd double check that the wires that carry the brake light current into and out of the turn signal switch (via the steering column harness) are plugged in and making good contact.  If either of those wires come loose, you'll get exactly the same symptom.

Also, if you have a test light or a meter, verify that 12 volts is getting to your brake light switch - if not, double check that fuse, especially the clips that hold the fuse.   It is very common on old cars for the fuse to check out fine, but not to be making good contact to the holding clips.  Test for 12 volts on the fuse holding clips on both ends of the fuse - all those points should have 12 volts on them.

Dick

---------- FOLLOW-UP ----------

QUESTION: I believe the fuse doubles for the back up lights and they work fine, i did put a test light to the brake switch wires and got nothing.I also put a test light to the fuse and got nothing.Do i ground the test light to one end of the fuse and touch the other side or do i ground it some where and touch one side of the fuse clip? Thank you very much for the help..Henry

Answer
I don't have a wiring diagram for your car, but it would be pretty unusual for the brake light fuse to be shared with the backup lights - more typically, the brake light fuse is shared with the interior lights or the dash lights, in order to alert the driver immediately if the brake light fuse blows out.  The fuse holder for the brake lights should be labeled "BK LTS" or (something like that) so you can identify it.  You may have to crawl under the dash with a flashlight and a magnifying lens to read the labels, if you are an old geezer like me!

The way to check with your test light is to put one lead from the test light on a known good ground point, which has to be bare metal and bolted to the body metal or frame somewhere.  Typically, you can find some bare metal in the structure of the dash supports.  Sometimes, just clipping the ground lead onto the ignition key (key in the switch!) provides a good enough ground.  Then put the other lead from the test light (or the tip of the sharp probe if you have a store-bought type test light) on the point you want to check.   If you do this on the fuse panel, you can see which fuses are good and making good contact with the mounting clip very easily.  Also, you should check those wires on the brake light switch the same way (with one lead grounded, and the other on the point to be tested).  When working under the hood, I use the negative battery post as my ground connection, and check my test light by touching the probe end to the positive post - if it lights up, I know I have the ground lead well grounded.  One of those wires on the brake light switch is supposed to have 12 volts on it all the time (if the fuse is good) and the other should have 12 volts only when someone is stepping on the brake.

On some cars, the key has to be on for the brake lights to work - I don't think this is the case with a 64 Impala, but just to make sure we aren't fooling ourselves, if you find no 12 volts on the brake light fuse either end, try turning on the key before we make a mistake here.



Dick