I finally got around to replacing the driver's side window regulator on my Dad's '72, but now the window only goes down. If I reverse the wires and push the switch down, the window goes up, so the motor is fine.
A volt meter shows the wires are getting 12 volts in either direction (one the reverse of the other), but under load the down switch drops less than a volt while the up switch drops to 6 volts (and the motor doesn't budge). So I'm thinking there's some kind of voltage inverter that needs replacing. Is this correct? And if so, where is it?
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