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1991 alternator/voltage regulator problems

Hans voytek

New Member
So, the alternator on my 1991 isn't charging my battery. I put a brand new battery and alternator in, still didn't fix it. I pulled my cluster and found that the ribbons leading to my battery indicator lamp are a bit bashed up. Anybody know how to repair those ribbons, if that's even the problem. Or if I can just bypass my cluster at my voltage regulator or at the harness behind my cluster? Thanks. Basically any way I can fix this problem. Thanks
 

Sawmill

Old and tired
My car is older but I had the same trouble back in '85. Turned out to be a burnt connection between the alt and the reg; replaced with a crimped butt connector.
A multi-meter is the tool you need. There are tutorials available online that can show better than I can tell the way to test the wires and connections.
My wife's 82 has the same connector replaced as well, so I think bad wiring here is not uncommon.
 

Hans voytek

New Member
My car is older but I had the same trouble back in '85. Turned out to be a burnt connection between the alt and the reg; replaced with a crimped butt connector.
A multi-meter is the tool you need. There are tutorials available online that can show better than I can tell the way to test the wires and connections.
My wife's 82 has the same connector replaced as well, so I think bad wiring here is not uncommon.

The voltage regulator is part of the alternator, if I'm not mistaken. And I have a new alternator which comes with a new reg. Is it the connector that connects to the voltage regulator you're talking about?
 

Sawmill

Old and tired
My manuals don't cover your model year, so I don't have a schematic handy, but juice must leave the alternator and get into the system. The voltage regulator is going to require a connection into the system so it can measure existing voltage and tell the alt how much juice to produce.
I'd look hardest at the heaviest wire leaving your alternator. With a meter one may measure voltage being produced at the alternator, while the engine is running of course, should be in excess of 12 volts. If this is right then you can search along the circuit for the fault. On very old machines the power from the generator passed through the amp guage, but I doubt the guage cluster ribbon could handle such a load.
 
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