1. Home
  2. Automotive Technologies
  3. Cadillac Alternator Problem Re-visited

Cadillac Alternator Problem Re-visited

Hello:

Recently, I posted a message in this newsgroup regarding an alternator voltage fluctuation problem on my 1989 Cadillac Eldorado.

I was asked to do some node voltage checks to see if I had a faulty ground somewhere. The grounds seemed to be OK, but the wire from the alternator output to the battery + terminal has a resistance of about

4 ohms. This seems high for such an otherwise low impedance wire, so could this be the source of the voltage fluctuation? Is this wire going through a relay or switch of some kind, or is it going directly to the battery? I can't see where it goes, due to the crowding of other components in the area.

Can I just bypass this wire with a heavy guage wire of my own, directly from the alternator output to the battery?

Thanks!

Steven

Reply to
Steven C.
Loading thread data ...

Steven, I don't have direct experience with that particular car, but I do own a Reatta which has given me a bunch of electrical surprises, and maybe some of what we Reatta owners have experienced could help you.

The Reattas have battery cables with up to 3 separate cables going to the battery. One goes to the alternator, one to the starter, and one to the electronics.

These cables often corrode internally, and lose contact. You can, to some degree or the other, peel the covering off the battery terminal end of the cable and clean the individual connecting surfaces. Maybe yours is similar. This could be an explanation for the 4 ohms resistance, which is quite a lot in a circuit like this one.

The starter cable does not go through a relay in this case, but the starter solenoid voltage does. If the theft deterrent system is activated, the starter solenoid does not work.

I had some custom cables made for my car, since I didnt want to pay the price GM wanted nor did I want the same type of technology.

Maybe this does not apply at all, but hope you solve your problem.

Reply to
<HLS

You are describing a bad connection.

The main 10 ga alternator wire goes to a 14 ga fuse link wire which bolts onto the starter solenoid. Very likely the connection at the starter solenoid just needs to be cleaned.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

"Steven C." wrote:

Reply to
Mike Romain

Awesome. Thanks for the info. I'll try to find that connection

Thanks again;

Steven

Mike Roma> You are describing a bad connection.

Reply to
Steven C

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.