Expert: Rob Painter - 5/18/2011

Question
I have a 1983 cadillac seville and for some reason my trunk wont lock, my power seats wont move, my power locks wont lock and my horn honks but its more like a faint beep you would hear on a childs toy! I am under the assumption that this problem has something to do with the fuses. I have already had 2 mechanics tell me I need to replace a relay for each, but I want another opinion.

Answer
Hello,

I am known for my avid critisizm of guys that call themselves mechanics offering suggestions like this and if they felt the problem could be corrected by changing the relays; why didn't they?

Especially since not one, but two offered this suggestion. One needs to realize that relays rarely fail, and then the answer is multiple relays?

The first problem is that it is a very old car. No knowing how many hands have been in it and what for creates a problem. Another problem is region of the country. Has this car been subjected to road salt?

Are there any water leaks in the car? Has the car EVER been subjected to high water in which the carpeting was soaked?

These are the first considerations before tearing into a problem like this.

Next--you need to have a factory electrical service manual for circuitry and wiring, so you know what all is on each circuit. Working on this car by a guess (which your two mechanics are offering you very questionable opinions on) will just cost you money and frustration.

Now, as for your horn (which is on a different circuit than the trunk, power seats and locks: You probably have a blown out horn. This car comes with not one, but at least 2. You need someone pushing on the horn and as you are checking the connector on each horn with a test light.

You did not say if you bought the car with these problems or if they just all came about.

For checking the seat, the best way is to remove the seat bolts so you can tilt it backwards. I may be incorrect, but isn't the sat switch on the door panel on this car?

Again, using a test light, you will operate the switch (doesn't matter which way and see if you have power at each connector. You could even save yourself that trouble to see if there is constant power going into the seat motor in the first lace. If not, you need to find out why.

Since everything is fed through the driver's door, it was very common for the wires to break inside the boot at the front of the door4 at the pinch point, which requires one heck of a lot of work to repair.

If you have constant power going to the seat and no power going to the different positions of the motor, a module could be defective. If you have power going to different seat positions, then you need either a motor(s) or the cable transmission. I have never seen a bad seat relay!

The trunk--you say it won't lock. What do you mean? The pull down isn't working? A very common problem and more trouble than its worth. If you remove the trim at the lower part, there is a 15 amp in line fuse. Check it. If good, make this close manually by adjusting the latch and it will close like a regular trunk lid. Saves a lot of headaches!

You state the locks won't lock. Chances are very good that the switch is junk and when you get that far we can discuss.

I have owned many 80s Sevilles and Eldos and know these cars pretty well. There are other possibilities as far as electrical causes too, but these are the obvious and not the relays and nothing to do with fuses.

If you sense a little frustration it is because I am very good with this stuff and all too common there are the "mechanics" that show just how ignorant they are and yet people would place me in the same catagory as these goofs.

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