Mechanics

ALTERNATOR / CHARGING PROBLEMS

1993 Volvo 940

Electrical problem
1993 Volvo 940 V8 Two Wheel Drive Automatic 140, 00 miles

I replaced my battery, and had the original Volvo atlernator rebuilt. Battery still drains with engine running, ON OCCASSION. Intermittent problem. When idiot lights (many of them) come on, I check the alternator output and get around 12.0 volts. When idiot lights are off, the alternator is charging fine and the voltage is 14.2 to 14.4.

The rebuild shop assures me the alternator is good and that the voltage regulator was replaced during the rebuild.

My alternator has a large red wire, a blue ground wire, and a small red wire with a female clip connection on the end.

My ground seems good, so I assume that it has something to do with the small red wire. I assume that this small wire feeds an external " excitor" and sends a message to the to the idiot light as well somehow.

I'm wondering, does this wire typically go other places first such as a relay, a circuit board, the starter, the ignition, etc. Before it gets to the idiot light?

Also wondering if you think that this is most likely be a loose wire somewhere, or a circuit board or an exciter relay (if there is such a thing) that is going bad.

If a circuit board or relay, how and where would I most likely find these components?
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Daculadad
January 10, 2008.



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