The wiring between the door hinges is okay if the passenger windows work from the driver's switch assembly. For the driver's window, the easiest way to test it is to test for voltage right at the motor connector. To be accurate, that testing should be done with the motor plugged in. If that is difficult to do, you can measure the voltages with the motor unplugged, as long as you understand if 0 volts shows up when it should be 12 volts, there's a switch or wiring problem, but if 12 volts shows up when it's supposed to, we have to get a little more involved with additional testing to be sure we found the right voltage.
If you can't get to the motor easily, back-probe the red / yellow and red / black wires right at the switch connector, (one meter probe in each wire at the same time). You should find 12 volts when you activate the switch one way, and minus 12 volts when you switch it the other way. If you have that, suspect the motor.
Another clue is to listen for any noise the motor makes when you activate the switch. If you hear a little groaning or crunching noise, the regulator likely uses a system of cables and plastic pulleys, and the cable is coming apart.
Aug 20, 2017 at 10:57 PM
