656d ampp light stays on

Anonymous-0 · Jun 19, 2012

1972 656d, wiring looks real good and original. Amp light started staying on three weeks ago. Starts everyday battery has not seemed to lose charge even though i glow plug and start. Voltmeter shows 12.6 at battery. Unplug regulator and light stays on, unplug alternator and it goes off. Pulled alt and shop says good. Any suggestions

Janicholson · Jun 19, 2012

External VRs are mechanical (if OEM style). They go bad just as do Gen Regulators. Were it mine, I would look for a compatible solid state replacement. Jim

Owen Aaland · Jun 19, 2012

(quoted from post at 12:45:02 06/19/12) External VRs are mechanical (if OEM style). They go bad just as do Gen Regulators. Were it mine, I would look for a compatible solid state replacement. Jim

Most likely cause is a problem in the relay circuit, shown by the dashed line. The relay is what turns off the light. With the alternator running you should have about half the battery output terminal voltage on the R terminal. Check for the same voltage at the #2 regulator terminal. If you get the voltage at the regulator then either the relay in the regulator is not closing or the contacts are dirty.

656d ampp light stays on

Anonymous-0

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Janicholson

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Owen Aaland

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