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Voltage Regulator

388 Views 6 Replies 5 Participants Last post by  Hoojio
My generator warning light will not go out when my engine is running, even at high engine speed. My battery has a good earth.

I have just fitted a new Mexican Bosch regulator to my 1971 1200 Beetle. 12V system, wired it up the same as the old one. I tested the dynamo before fitting the regulator and i was putting out a no load voltage of about 38V at high engine speed.

I have a blue wire running from the bottom right terminal into the loom running to the dashboard. The live feed and the +ve battery connection running from the top right terminal. The D+ from the battery and a brown wire are connected to the botom left terminal. The top left terminal has a green wire connected to it. And finally I have connected a grey wire, that I assume is the earth, to the bracket of the regulator which is bolted to the car.

Does anyone know what is going wrong?
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hope that may provide you with more information than trying to explain it.
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Try clamping a wire (jump lead perhaps?) to the body of the regulator and run the other end of the wire directly to the negative terminal of the battery (be careful not to touch any of the terminals on the regulator)
If the light goes out, the metal where the regulator is screwed to the car is corroded and needs cleaning.

If not, have a look at the dynamo brushes - does the commutator (the bit with all the copper tracks that the brushes touch) have a deep gouge in it? If so, take the brushes out and file off the corners until they sit neatly in the gouge. That should sort it out.
wow how cool is that pic!
Thanks guys! I disconnected the grey wire and taped it up, connected the brown wire to the bracket of the regulator and cleaned the screws holding the regulator on to the car and it's all working properly now. :)
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