Window regulators and motors
At a glance: A power window has a switch, motor, regulator and glass. If nothing happens at the switch, suspect the switch, motor, fuse or wiring; if the motor runs but the glass does not move, the regulator has failed, per the shop[1][3].
What makes a power window work?
The shop’s power window page lists four main parts: “the switch, the motor, the regulator and of course the window itself”[1]. The regulator is the mechanism inside the door that carries the glass up and down; the motor drives it; the switch, fuse and wiring deliver the power[2].
Which kinds of regulator are there?
| Type | How it works | Common failures (shop’s account) |
|---|---|---|
| Manual | A crank handle turns a rod that protrudes about an inch from the door | Cable binding or broken brackets; uncommon |
| Cable-style power | A motor winds a cable on a single arm; compact enough for small doors | Weak motors and cable binding; a ruined cable usually means a whole regulator |
| Scissor-style power | Two arms crossed in an X with a central pivot, moved by the motor through gears | The motor, and gears worn flat, some made of plastic |
From the shop’s article on regulators and motors[3].
How is the fault narrowed down?
The shop’s rule of thumb: if pressing the switch does nothing, the switch or motor is the likely cause, although a fuse or wiring fault is possible; if the motor can be heard running but the glass does not move, the regulator is at fault[1]. Its regulator article adds that a failing motor “often” makes “a sort of clicking or low pitched hum”, and that if the motor and regulator can both be heard moving, the window may be off its track or the gears “eaten away”[3].
What does a proper repair include?
According to the shop’s article, a good repair supplies the regulator, greases all the gears, and tests the motor with positive and negative 12-volt connections during installation[3]. The power window page says the shop offers same-day service “in most cases”, a lifetime warranty on labour, and a choice of parts at different prices[1].
New, used or aftermarket parts?
The shop offers “dealer parts, used original parts, or aftermarket options”[1]. Dealer parts match the original but cost the most; used original parts can be the cheapest way to get an exact match on an older car; aftermarket regulators and motors vary in quality. The power window page says the shop will explain the options and the price before the work[1].
Does the glass need replacing too?
Not usually. A regulator failure can leave the glass loose or dropped inside the door, but the door glass itself, normally tempered, is reused unless it is broken. Tempered glass breaks into small, blunt pieces when it fails, so a broken door window means clearing fragments from inside the door as well as fitting new glass[4][5]. Door glass “comes in many shapes and sizes”, the shop notes, and most modern cars raise it with an electric motor[5].
Is there a safety rule for power windows?
Federal Motor Vehicle Safety Standard No. 118, administered by the National Highway Traffic Safety Administration, governs power-operated windows, partitions and roof panels, including when they may close, to reduce the risk of trapping a hand or a child[6]. A repaired window should close smoothly and, where the car was built with it, keep any automatic reversal feature. Ask the shop to test the window through its full travel before you leave.
Related reading
- What the shop does
- Glass terms
- Reading the glass label
- OEM and aftermarket glass
- Jacobs Low Price Auto Glass
Sources cited
- ^ a b c d e f Power Window Repair. Jacobs Low Price Auto Glass (lowpriceautoglass49.com). Verified 9 November 2026.
- ^ Power window. Wikipedia. Verified 9 November 2026.
- ^ a b c d Window Regulators and Motors Explained. Jacobs Low Price Auto Glass (lowpriceautoglass49.com). Verified 9 November 2026.
- ^ Tempered glass. Wikipedia. Verified 9 November 2026.
- ^ a b Specialized Glass Repair Dallas. Jacobs Low Price Auto Glass (lowpriceautoglass49.com). Verified 9 November 2026.
- ^ 49 CFR 571.118, Standard No. 118: Power-operated window, partition, and roof panel systems. Electronic Code of Federal Regulations. Verified 9 November 2026.
Common questions
Why does my car window make noise but not move?
If the motor runs but the glass does not move, the regulator is the usual cause, per the shop.
What is a window regulator?
The mechanism inside the door that raises and lowers the glass.
Can a used regulator be fitted?
The shop offers dealer, used original and aftermarket parts.