A regulator is a mechanism that is on the inside of the car door panel that moves the window up and down.
Regulators vary in function depending on the year, make, and model of a vehicle, as they are either powered manually or electrically. If the window’s regulator is a manual mechanism, the window is rolled up and down by a spinning leaver by use of the occupant’s hand. An electrically powered window regulator is connected to a motor that will move the device allowing the window to be rolled up and down by the touch of a button, or the push of a switch.
If your window is not rolling up or down and you hear a sort of humming noise from the potential motor trying to run, the regulator needs to be replaced. If your glass has fallen into your door panel and will not go up or down, the regulator needs to be replaced. Also, if the window moves at a slant or does not properly shut, the regulator may need to be replaced.
A power window master switch is a switch connected to the driver door in a vehicle. The master switch contains multiple different keys, depending on the vehicle, there may be two or more keys that control the movement of the vehicle’s windows. There may also be keys that move the side mirrors, as well as unlock or lock the doors from the inside.
If a window does not roll up or down by pressing the key on the master switch, but the window does roll up and down from the switch physically on the door, then the master switch is malfunctioning and needs to be replaced.