What is a door lock relay?
A door lock relay is an electromagnetic switch that controls your car’s power door locks. When you press the lock button, the vehicle’s central locking system sends a signal to the relay. As the relay receives this signal, it activates its electromagnet, mechanically moving the door lock to the locked or unlocked position.
When should I replace the door lock relay on my car?
The two most common signs of a faulty door lock relay are:
The door locks function intermittently: One of the first signs of a bad door lock relay is locks that only work intermittently. If your door locks work one second and not the next, or it takes several tries to lock or unlock the doors, you may need a relay replacement.
The door locks stop working altogether: Power door locks that completely stop working are often a sign of relay failure. When the relay fails, it cuts power to the entire lock system. If your car has door lock cylinders, you can still access the vehicle with your key. But if your car has keyless entry, you may find yourself unable to enter the car.
Keep in mind: These issues may not always indicate door lock relay failure. Other electrical issues can cause similar symptoms so it’s always a smart move to visit a professional mechanic for an accurate diagnosis.
How often should I replace my door lock relay?
There is no set replacement schedule for a car door lock relay. The relays are designed to last for many years, and yours may even last for the vehicle’s life.
But over time, relays can wear out and will need to be replaced. You’ll know it’s time to replace yours if your power door locks work intermittently or stop working completely.
Can I replace my door lock relay myself?
Generally, you don’t need years of experience working on cars to replace a door lock relay—and most DIYers can replace a relay easily and quickly.
That said, depending on your vehicle, it may be best to leave a door lock relay replacement to a professional mechanic. This is because door lock relays are typically located in one of four places: in the engine bay fuse box, in the driver-side cabin fuse box, behind the stereo, or behind the passenger-side airbag.
If your door lock relay is located behind the stereo or airbag, it will be significantly more complicated to replace. If you’re not an experienced home mechanic, you should let a professional handle the replacement.