Cadillac Repair: 1976 Coupe dewville, forensic evidence gathering and documentation expert consultant

Question
When i purchased the used vehicle the horn did not work; the driver's seat motor quit working soon after.  The electric locks and trunk motor have stopped working and when I examined the circuit breaker for what the shop manual designated as the "horn, driver's seat, electric locks and top motor"  the circuit breaker was hot as a toaster and the battery was drained.  Is this circuit breaker the propblem or a symptom?  How do I get a replacement?

Answer
Hello,

I think what you need to do is find the parasitic draw and since your dealing with a CB instead of a fuse it will be a little more inconvenient.

Sure sounds like a lot to be on one breaker, but here is what I suggest. They did lots of weird things back then. What you need to do is get a test light. Remove the positive cable at the battery. Place the clamp for the test light on the positive battery terminal. The other end to the positive cable. The test light will be on.

Remove the connector from the trunk motor. see if the light goes out. If it does, the trunk motor is no good. If the test light stays on, plug it back together. Go under the dash and disconnect the turn signal switch and check the test light. If still on, plug it back in. Go to the top and disconnect the motor. Then you are going to go on the driver's kick panel, remove it and find the connector for the locks, windows etc and disconnect it.
When that test light does not light anymore, you will have found your problem.

I would also suggest removing the dome/courtesy light fuse and trunk bulb while doing this test because you will probably leave the door open as well as the trunk, because if you forget to remove them and have the dome light on with the door open, the test light will stay on.

Make sure if you use electrical tape to hold the pointed end of the test light to the cable that none of this touches any metal.

I do not know what years that CB was the same, so I can't help you on the replacement. The CB is probably the symptom here and may now be fried, but you need to make sure now that something is not defective because you could possibly have a fire.

Good luck and let me know what you find.

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