Your car’s door locks are a key part of your car. While the door locks don’t affect how your car runs, it is still nice to have ones that work. That is because your door locks keep the things inside your car safe and also keeps your car as a whole safe.
Sometimes though they stop working for various reasons. If they all stop working at once, then it is pretty easy to find the problem. It is generally a blown a fuse or just a dead battery in your key fob, but what I only one isn’t working.
Well, in this article we will look at what it means when only the driver side power door lock won work, but the tips in here apply to your car no matter which door isn’t the one locking.
How the door lock works?
To understand why only one door may not be locking properly, it is important to understand how your door locks work. Both the kind that have the switch tip thing that opens and closes or the type that have the push thing that goes up and down, they both work the same way.
When you press the button on your key fob to lock the door or press the button inside the car to lock the door, it sends a signal to the car to engage or disengage the locks.
More specifically it sends a signal to the door lock actuator which takes this signal and turns on a motor to activate the lock. When just one door lock isn’t working it normally means that you have something wrong with this system.
Things to check
So, now that you know you have something wrong with this system it is time to start checking it. The first and easiest thing to check is to make sure that nothing is obstructing the door lock from engaging.
If dirt or grim gets in there, then it might prevent the locking part from moving and locking. A good way to know if that is the problem is to listen when you press the locks and see if you can hear the broken door trying to engage.
The best way to clear out the lock mechanism without taking it apart is to spray some lubricant into the lock. Something like WD40 will help lubricate it and break up any obstructions. This might be a simple and easy fix to your problem.
After lubricating the lock if it still doesn’t work, then you will have to dig deeper into the door to try to fix it. This will mean taking the door panel off to get inside of it so you can get to the actuator and motor.
Once you have the door panel off, you can see if there is any visible damage to the parts in the gearbox. Sometimes a gear from the motor can break, and this could be the cause of the problem.
If you see loose pieces in the door lock area or the gear is missing teeth, then you will just need to replace it. If there is no visible damage, then you will have to go into real deep testing.
Testing the actuator
The first thing that you should test is the actuator. The best way to do this is to remove the wires connected to it and then take a battery. Twelve volts is best, but a 9-volt battery is normally easier to get.
With a 9-volt battery wire, a couple probes to it and then touch the probes to the input connection on the actuator. If the actuator is good, then it should try to engage the lock and make some sound.
If the battery need to recharge, highly recommend you use best battery tender to recharge your car battery.
If the actuator is dead, then it won’t do anything, and you have found the problem. If the actuator is bad, all you will have to do is buy a new one.
A lot of times you will have to order a new one, so you might have to go a few days without your lock working and your door apart. If the actuator is good though, then you can move on to testing the other possible issue.
Testing the motor
The other possible issue is a dead motor. At this point that is the only thing left to check. You can check it in the same way as the actuator. Connect some wires to a 9-volt battery and then connect the probes to the motor.
A working motor should make sound and try to spin. If it doesn’t, then it is dead and needs to be replaced. Again, just buy or order a replacement part and install it. I
f the motor isn’t bad and none of the other things are bad, then you have or had a problem with how the lock was put together. Reassemble the lock, and it might work again. The problem might have been a bad connection that you just didn’t notice.
Why only one lock go bad?
You may be wondering why only one motor or actuator failed though if you lock all your doors the same amount of times. Well, since these parts are moving, they happen to fail at different rates.
This is especially true for the plastic pieces like the gears because even though they are the same, they all had different variables in their production. That is why one lock may break and none of the others even with equal use.
So, now you know why only your driver side door isn’t working. You know that locks are made up of gearboxes, motors, and actuators and any one of these parts can break at any time within a single door.
Now you know what to look for though if you only have one lock that isn’t working. You know to start with lubricating the lock and see if that fixes it before taking it apart.
If you have to take it apart though you now know to look for broken gears in the gearbox and how to test the motor and actuator to see which one might be bad. You then know how to replace it, so the next time your driver side lock isn’t working, or one of your other locks isn’t working you will be able to troubleshoot it and fix it yourself.