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On 28 May 99, at 8:56, Nathan Jacobsen wrote: > This is interesting. Can anyone explain the electrical circuit and how the > lamp lights without a ground? One side of the lamp comes from theÕÄth or input to the VR. The other side comes from the battery via the ignition switch. When you turn on the key the second side gets 12 V but with the engine not running the gen side is just like a ground (through the inactive generator.) So the bulb has 12 V across it and it lights up. When you start the car and everything is running fine there is 12 V at the gen output AND 12V at the ignition switch, so the voltage drop across the bulb is zero and there is no light. If something fails, you still have 12 V from the ignition switch, but the gen output goes to zero and the bulb goes back on. Jim - ******************************* Jim Adney, jadney@vwtype3.org Madison, Wisconsin, USA ******************************* ------------------------------------------------------------------- Unsubscribe? mailto:type3-request@vwtype3.org, Subject: unsubscribe