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Charging

 
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TeamDFL



Joined: 14 Oct 2000
Posts: 1
Location: Apex, NC, 27502

PostPosted: Sat Oct 14, 2000 6:38 pm    Post subject: Charging Reply with quote

My alternator will not charge up until I rev the engine over 2500rpm. The battery light stays on and I have confirmed the lack of charge with a volt meter. I have been told that there is some problem with an interface between the light and the SI board. Is this true? Is there a way I can bypass it with a resitor or other Kluge? Or is it, as I suspect, a faulty voltage regulator?
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bimmer84



Joined: 21 Oct 2000
Posts: 4

PostPosted: Sat Oct 21, 2000 3:42 am    Post subject: Charging Reply with quote

TeamDFL:

You are having the same charging problem as I am. I think I have found the answer, but I haven't had a chance to work it
out yet. Is your car a 1986, or earlier? Here is a quote straight from my Bently service manual. "On models built up to late
1986, a burned out alternator warning light will prevent the alternator from charging. On late 1986 and later models, a
resistor is wired in parallel with the alternator warning light. This will allow current to reach the alternator during starting
when the warning light is burned out."

In my case, there are two posts on the back of the alternator...one large wire to feed the battery, and a small wire that brings
juice to the alternator when you turn your ignition switch. The ignition circuit passes through the warning light on it's way
to the alternator. This is the circuit that "energizes" the alternator to begin charging (the same will happen when you rev the
engine high enough to energize it). If the warning light is burned out (and mine is) the juice never reaches the alternator to
energize the circuit.

This may be your problem as well.

Dean
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rduckwor



Joined: 09 Dec 2000
Posts: 41
Location: Bellevue, NE USA

PostPosted: Thu Nov 02, 2000 11:44 am    Post subject: Charging Reply with quote

My vote is a tired voltage regulator. Bimmer84 is correct in that the early cars required the ALT WARNING light as a link in the excitor current circuit. But if the bulb is burned out it obviously wouldn't light would it?

Easy to change the regulator/brush unit out on most of the alternators.

Good LUck,

Bob Duckworth
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bimmer84



Joined: 21 Oct 2000
Posts: 4

PostPosted: Fri Nov 03, 2000 8:07 pm    Post subject: Charging Reply with quote

Oops, sorry, I missed the part about your light being on. In my case, my light was actually ok, but the recepticle that holds the bulb wasn't making good contact with the circuit board, so the circuit wasn't complete, and the bulb did not receive current. I used a pice of 1500 grit emery paper to clean the contacts. Everything works fine now.
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