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Tue Sep 04, 2018 8:43 pm

After driving my buggy around yesterday the generator light came on when I turned the car off. When I turned it back on the light turned off. Had to disconnect the battery last night.

Poking around today trying to figure out what happened I noticed the D+ wire (between the generator and regulator) was hot to the touch when I reconnected the battery (ignition off). I tested the generator (it puts out 50+ volts) and polarized it but when I reconnected the wires the generator light lit up again (keys not even in the ignition) and the D+ wire got hot again.

I'm guessing it's a bad regulator? Not sure where to go from here as far as troubleshooting.

Tue Sep 04, 2018 9:00 pm

randreas wrote: After driving my buggy around yesterday the generator light came on when I turned the car off. When I turned it back on the light turned off. Had to disconnect the battery last night.

Poking around today trying to figure out what happened I noticed the D+ wire (between the generator and regulator) was hot to the touch when I reconnected the battery (ignition off). I tested the generator (it puts out 50+ volts) and polarized it but when I reconnected the wires the generator light lit up again (keys not even in the ignition) and the D+ wire got hot again.

I'm guessing it's a bad regulator? Not sure where to go from here as far as troubleshooting.

Start here.
http://www.vw-resource.com/alternator_generator.html

Tue Sep 04, 2018 9:29 pm

Your voltage regulator cut-in contacts are stuck closed which causes the battery to try to run the generator like a motor, if you were to remove the fan belt you'd find the generator would start spinning.

You may be able to unstick the contacts by giving the VR a sharp rap with a screwdriver handle, but it's most likely you'll need to replace the regulator to effect a long term repair. In the mean time you should leave the battery disconnected else you run the risk of damaging the generator and battery.