Glossary term
car door
The powered door on the lift car itself, driven by the door operator and responsible for opening the landing door as well.
What it means
The car door travels with the car. It is the one that has the motor, so it does the work of opening and closing at every floor, and it drags the landing door with it once the two are engaged. Its edges carry the detection devices that stop it closing on a passenger. Some older and smaller lifts have no car door at all, only a landing door, which is why the shaft wall appears to slide past as you travel.
Where you see it
On the front of the car. What you see as one door when you get in is usually two doors — car and landing — moving together a few centimetres apart.
How it works
The door operator drives a belt or arm that opens the panels, and a linkage on the car door engages the landing door lock at the same time. The controller watches the door position and the detection devices, and it will not start a journey until it sees the closed-and-locked signal from both doors.
Closing force and speed are set deliberately low, and detection devices reverse the door on contact. If the door repeatedly meets resistance, most controllers reduce speed, try again, then park with the doors open and register a fault rather than pushing harder.
Why it matters
Door faults are the largest single category of lift callouts. Most of them are mechanical rather than electrical: a track that has collected grit, a worn hanger roller, a bent sill, or something dropped in the gap between car and landing.
Commonly confused with
The car door and the landing door look like one door because they move together, but only the car door is powered. The car door carries a vane or coupler that picks up the landing door and drags it along. If a lift opens on one floor and not another, the car door is usually fine and the problem is at that one landing.
Wear, service and lifespan
Car doors run thousands of cycles a week, so their rollers, tracks and door shoes wear faster than almost anything else on the lift. Service work means cleaning the sill track, checking roller play, and re-timing the open and close so the door neither slams nor crawls. Most door faults are found here before they turn into a shutdown.
Signs to watch for
- The door reopens two or three times before it manages to close.
- It closes fast and then stops with a bang.
- It jams part-open with the lift out of service.
- You can hear rubbing or squealing as it moves.
- The door closes but the lift does not start.
Troubleshooting car door
Doors open then immediately close again on every floor
What it usually means: The controller is not getting a clean fully-open signal from the door operator
Safe check: Watch whether the door reaches the full opening or stops short, and time roughly how long it stays open.
A grinding or dragging noise along the floor as the door moves
What it usually means: Debris in the sill track, or worn door shoes
Safe check: Look down at the sill groove for grit, coins or packaging. Report what you see; do not dig it out with tools.
The door judders in the last few centimetres of closing
What it usually means: Door timing or the coupling with the landing door needs adjusting
Safe check: Note whether it happens on every floor or one, and report the floor numbers.
How to report it
Give the floor or floors, whether it fails opening or closing, and whether the lift still runs afterwards. Mention if anything is visible in the sill. Door calls are the most common lift call, so this detail is what decides whether an engineer brings door parts.
Ask us about car door on your lift
Tick anything you can see or hear from where you normally stand, add a note in your own words, and we will put it into the message below for you. Never open, force or enter any part of the lift to check.
0/800 characters. Please leave out personal details you would rather not email.
Get help by email
Tell us what your lift is doing
Send the make, model, error code and what the lift does now. We reply by email and point you to the right help.
Related terms
Definitions that usually come up alongside car door when you are describing a fault.
- door operator
The motor and gear on top of the car that opens and closes the doors and reports their position to the controller.
Doors and entrances
- safety edge
A sprung or sensitive strip on the leading edge of a door that reverses it the moment it touches an obstruction.
Safety devices
- light curtain
An array of infra-red beams across the door opening that holds the doors open while anything breaks a beam.
Safety devices
- landing door
The door in the wall at each floor, locked shut until a lift car is present and level behind it.
Doors and entrances
- interlock
A lock and switch combined, so a door cannot be opened unless the car is there and the lift cannot move unless the door is locked.
Safety devices