Symptom
Central locking not working
The doors will not lock or unlock together — from the fob, from the button, or from the key.
The pattern is the diagnosis, so notice which doors and which method. One door misbehaving while the rest work points at that door: its lock motor, its switch, or the wires crossing the rubber concertina between door and body, which flex every time the door opens and break inside insulation that still looks perfect. All doors failing at once points upstream — the body control module, its supply, or the fob receiver.
A fob that works sometimes, or only close to the car, is usually a fob battery rather than a car fault, and it is worth eliminating first because it costs almost nothing.
Two consequences matter more than the inconvenience. A car that is not reliably locking is not reliably secure, and the mechanical key blade exists for exactly this — use it and check the car is actually locked before walking away. And a car that believes a door is open often will not go to sleep, which flattens the battery over a few days of standing; if yours has needed jump-starting after a quiet week, the two faults are probably one.
Also described as: doors wont lock, central locking failed, key fob not working, remote locking not working, doors unlock on their own, cant lock the car, قفل مرکزی کار نمیکند, ریموت قفل کار نمیکند, cierre centralizado no funciona, no abre con mando, seguros no funcionan, no cierran puertas con mando, القفل المركزي لا يعمل, الريموت ما يفتح, الأبواب لا تقفل بالريموت
What this usually means
The pattern is the diagnosis, so notice which doors and which method. One door misbehaving while the rest work points at that door: its lock motor, its switch, or the wires crossing the rubber concertina between door and body, which flex every time the door opens and break inside insulation that still looks perfect. All doors failing at once points upstream — the body control module, its supply, or the fob receiver.
A fob that works sometimes, or only close to the car, is usually a fob battery rather than a car fault, and it is worth eliminating first because it costs almost nothing.
Two consequences matter more than the inconvenience. A car that is not reliably locking is not reliably secure, and the mechanical key blade exists for exactly this — use it and check the car is actually locked before walking away. And a car that believes a door is open often will not go to sleep, which flattens the battery over a few days of standing; if yours has needed jump-starting after a quiet week, the two faults are probably one.
The door loom is worth understanding because it explains so much of this group. Every wire to a door — lock, window, mirror, speaker, lamp, and on some cars the airbag circuit — passes through a flexible boot that bends thousands of times. Conductors fatigue inside intact insulation, so the wire looks perfect and reads open only when the door is at a particular angle. That is why a window and a lock failing on the same door is one repair rather than two.
Working through it
| What you find | Likely cause | How to confirm it | What fixes it |
|---|---|---|---|
| One door only, others fine | That door — its lock motor, switch, or the loom in its flexible boot | Operate the door's window and mirror too. Two failures on one door names the loom rather than the components. | Repair the loom inside the boot with enough slack to flex, or renew the lock actuator. |
| Fob works intermittently or only very close to the car | The fob battery — the cheapest possible cause | Try the spare fob and fit a fresh battery. Eliminate this before anything else. | Renew the battery. If both fobs behave the same, look at the receiver. |
| All doors fail together, key and button too | Upstream — the body control module, its supply, or a fuse | Check the module's fuses and supply. All methods failing rules out the fob and the individual doors. | Repair the supply or the module. |
| Fob dead but the interior button works | The receiver or its aerial rather than the locking system | Both fobs failing with the button working isolates it to the radio side. | Repair the receiver or its aerial connection. |
| Battery flat after standing a few days | A car that believes a door is open and will not sleep — one fault, two symptoms | Check the door and latch states live. See the door-shows-open entry. | Repair the latch switch. Fitting a battery for this treats the symptom. |
| Locks cycle by themselves, or unlock on their own | Water in a latch or a door switch, or a failing module output | Check for water in the latch and its connector. Correlate with rain or a wash. | Dry, clean and seal, and repair the drain that let water in. A car unlocking itself is a security matter. |
-
One door only, others fine
- Likely cause
- That door — its lock motor, switch, or the loom in its flexible boot
- How to confirm it
- Operate the door's window and mirror too. Two failures on one door names the loom rather than the components.
- What fixes it
- Repair the loom inside the boot with enough slack to flex, or renew the lock actuator.
-
Fob works intermittently or only very close to the car
- Likely cause
- The fob battery — the cheapest possible cause
- How to confirm it
- Try the spare fob and fit a fresh battery. Eliminate this before anything else.
- What fixes it
- Renew the battery. If both fobs behave the same, look at the receiver.
-
All doors fail together, key and button too
- Likely cause
- Upstream — the body control module, its supply, or a fuse
- How to confirm it
- Check the module's fuses and supply. All methods failing rules out the fob and the individual doors.
- What fixes it
- Repair the supply or the module.
-
Fob dead but the interior button works
- Likely cause
- The receiver or its aerial rather than the locking system
- How to confirm it
- Both fobs failing with the button working isolates it to the radio side.
- What fixes it
- Repair the receiver or its aerial connection.
-
Battery flat after standing a few days
- Likely cause
- A car that believes a door is open and will not sleep — one fault, two symptoms
- How to confirm it
- Check the door and latch states live. See the door-shows-open entry.
- What fixes it
- Repair the latch switch. Fitting a battery for this treats the symptom.
-
Locks cycle by themselves, or unlock on their own
- Likely cause
- Water in a latch or a door switch, or a failing module output
- How to confirm it
- Check for water in the latch and its connector. Correlate with rain or a wash.
- What fixes it
- Dry, clean and seal, and repair the drain that let water in. A car unlocking itself is a security matter.
Codes that produce this symptom (20)
Listed with the codes that most typically present this way first — the likeliest place to start.
- U0501 Invalid Data Received From Door Control Module B Typical of this code Low
- U0502 Invalid Data Received From Door Control Module C Typical of this code Low
- U0503 Invalid Data Received From Door Control Module D Typical of this code Low
- U0504 Invalid Data Received From Door Control Module E Typical of this code Low
- U0505 Invalid Data Received From Door Control Module F Typical of this code Low
- U0506 Invalid Data Received From Door Control Module G Typical of this code Low
- U0514 Invalid Data Received From Mirror Control Module A Typical of this code Low
- U0515 Invalid Data Received From Remote Function Actuation Module Typical of this code Low
- U0531 Invalid Data Received From Rear Gate Module Typical of this code Low
- P04B5 Fuel Fill Door Stuck Open Low
- P04B6 Fuel Fill Door Stuck Closed Moderate
- U0516 Invalid Data Received From Door Switch A Low
- U0517 Invalid Data Received From Door Switch B Low
- U0518 Invalid Data Received From Door Switch C Low
- U0519 Invalid Data Received From Door Switch D Low
- U051A Invalid Data Received From Door Switch E Low
- U0521 Invalid Data Received From Door Switch F Low
- U0522 Invalid Data Received From Door Switch G Low
- U3005 Retained Accessory Power Moderate
- P04CB Fuel Fill Door Open Request Sensor/Switch Circuit High Low
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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