Fixing Your Car’s Central Locking System

Currently, most cars produced are equipped with a central locking system. These electrical systems allow the driver to remotely lock and unlock the doors and boot on a vehicle. In most cars, the central locking system can be controlled from inside the car, usually via a button insider the driver’s door, or with a key fob.

Over time, two major types of central locking have emerged in terms of functionality, namely: infrared and radio waves. Central locking by radio waves are most often used today. The key, as a transmitter, sends a coded signal to the receivers in your car via radio waves. This coded signal is compared to its own code to ensure a match, which will unlock or lock the vehicles central locking system.

What to do when your car’s central locking is not working

A selection of electrical rocker switches controls your vehicle’s central locking system. Car door locks can still be activated manually (by a traditional key in a lock method), but nowadays it’s more common to use an electronic key fob to activate the switches, also known as a central locking system. It’s easier, quicker and better for everyone involved: drivers and passengers alike.

How your remote central locking works

The mechanical explanation to describe your car’s central locking system function goes like this:

Your remote button sends a signal to the door lock relay.

The lock relay activates the lock actuator inside the door.

The lock opens and grants access to the vehicle.

The cost to repair central locking and to replace an assembly unit

The lock switch operates as the remote for the actuator. One of the problems with this is if the switch dies, the actuator has no way of being activated, and your locks are inoperable.

Given that most of these components are supplied as a complete assembly unit, repairing a central locking system is impractical, so replacement is more than likely your only option.

These complete units can be costly, so if you have to replace them in several or every door, your central locking repair costs can quickly escalate.

Regular use and wear and tear can lead to a central locking replacement

Your car’s central locking system will be used every time you use your car. With such frequent operation, including small parts and delicate operations, the switches and electrical components will eventually wear out, fail and require replacing.

Reasons why your car doors aren’t locking properly

Your mechanic won’t ever just jump in and replace the central locking units straight away. If your central locking system is failing, there could be a number of issues that must be investigated.

You could have blown a fuse

If one door works as it’s meant to, but another doesn’t, it could be something as simple as a blown fuse. Fuses cost next to nothing to replace, so they’re always worth checking before you start jumping the gun.

The key fob is faulty

If none of the door locks operate, then the problem could be with your key fob.These time and effort saving gadgets can be hooked up to a computer to troubleshoot and test. If it’s your fob failing to send a signal, it’s going to need replacing.

The key fob battery is dead

Before you arrange for a mechanic or garage to check your key fob or your central locking system, the first step should be to check your fob’s battery. It’s easy to overlook the most basic things, as we’re prone to thinking the worst from the outset.

So make sure it’s not the battery before you book an appointment to have your key fob tested.

Your door lock solenoid could have failed

If you are experiencing problems with one door/lock in your car’s central locking system, the solenoid in your lock might have failed. Central locking systems can be very complex, as they consist of many components. We recommend having your car inspected by a mechanic or booking a vehicle diagnostic if you’re having problems.

Broken or damaged electrical wires

A simple way to detect broken wires is to hold up the key fob and open and close the door repeatedly. A broken wire may be jolted into making a connection. If this is the case, you’ll get intermittent power to the locks when using the fob. This is especially common for the driver’s door, as it is usually used most frequently, making it vulnerable to damaged wiring.

Central locking repair costs

Typical costs to repair or replace your central locking system obviously depend on the make and model of your car. 

Central locking replacement can cost anywhere between £100–£300 for standard model vehicles with standard central locking systems. Fixter can save you around 15% on many dealer and independent garage prices when you choose us to take care of your problem.

Your central locking fitters will:

Test your door lock operation

Test all the fuses in each circuit with in your car’s central locking

Test the electrical relay

Decide on the best solution to repair any faulty door lock switches

Replace any malfunctioning central door locking units