How do you troubleshoot motorized windows in a car?

Answer 1

First try all of the windows up and down. Write down exactly which windows do not move in response to a switch. Mention whether they fail with the driver-side master switch, the switch by that window or both.

If the window is up and can still make a twitch up when you hit an up switch than you know the motor and its power is OK so your list of causes is cut down significantly. Even if the motor does not make the window twitch listen carefully with the engine off and the ignition on to hear whether there is a hum coming from the motor while you hold the switch down. Again that indicates power and that a switch is OK but doesn't say anything about the motor itself.