Modern cars rely on power door locks to allow you in and out. With the press of a button you can unlock the driver side door, or even all four doors in a vehicle. These locking mechanisms rely on something called the door lock actuator. It's inside your door and includes an electric motor, a linkage with gears, and a cable that extends a rod to operate the lock itself. When this actuator goes bad getting your door unlocked becomes quite a chore so you want to get it fixed as soon as you possibly can. The cost of replacing a door lock actuator is likely going to be between about $180 to as much as $700.
On average it seems like most cars that have a problem with the door actuator are going to end up costing around $200. However, the price can go up considerably depending on the make and model of the vehicle you have. For instance the cost of fixing the actuator in a Honda Civic is around $200 whereas the cost of repairing the exact same mechanism in something like an Audi will be upwards of $400 to $500 depending on where you get it repaired. An even more exotic car like a Lykan Hypersport or a McLaren M1 can cost you well over $700.
What is a Door Actuator?
A door actuator is an electronic mechanism that raises and lowers a rod that connects to your door lock. The motor in your actuator gets power from the battery so it can't work if you have no battery power left in your vehicle. When you press the button on your key fob, on the door itself, or punch in the electronic code depending on the kind of lock you have it sends a signal to the actuator telling you to either open or close the lock as necessary. A clutch will disengage from the gear so that you can lock or unlock the door manually inside the car or with the key for outside it if you choose to do that as well.
Because you can still manually use a key to lock and unlock a door when your door actuator fails it isn't necessarily any emergency problem that needs to be addressed right away, but it will definitely be annoying if it doesn't work properly any longer.
What Causes a Door Actuator to Fail?
Usually when a door actuator in a car fails it happens on the driver side because that's obviously the door that's going to get you as more often than the others. The most common cause for this to fail in your car is because it wears out from simple wear and tear over a long period of time because there are a lot of moving parts in here including gears and the retractable cable and it can also be an electrical issue.
If your actuator isn't getting the proper electrical signal any longer it won't be able to function. This can be a result of your battery being dead, or a fuse blowing as well. The mechanical linkages can wear out or latch assembly can prevent the motor from moving which causes the mechanism to stall.
Mechanical issues will be isolated to the single door in which the mechanical problem has occurred. If all the doors fail at the same time, then that is very likely caused by a defective switch or some kind or a blown fuse.
How Do I Know if My Door Lock Actuator is Bad?
There are a number of signs you can be on the lookout for that will let you know there's a problem with the actuator in your door before it gets so bad that you simply can't unlock it anymore. If you start experiencing any of these problems, you should get your car to a mechanic whenever it's convenient for you so that you can prevent the issue from going from bad to worse.
Because your door actuator is an electronic component, as it begins to fail it will typically perform in a very spotty manner. That means it will be working sometimes but not other times. Additionally if there are wiring or electrical issues then you might find that your door will have problems in which it seems to lock and unlock on its own or several times in a row even though you haven't pressed any buttons to make it do so.
This problem can be caused by not just an actuator issue but a frayed wiring harness in the door hinge. It's also possible that the bumper stop that prevents the lever from hitting as the lock raises and lowers has broken. When your lock is working normally there is a current spike when the lever hits his bumper at the bottom. If the bumper has failed, then the mechanism won't be giving the signal that the lock is actually finished doing its job. That can cause the door to unlock immediately after locking.
As we've said, the door actuator includes a motor, gears, a linkage, and a Rob that will raise and lower to lock and unlock your door. When those moving Parts begin to fail it works not unlike any other moving Parts in your vehicle when they begin to fail. You'll notice sounds from inside your door that are not typical to the way your car usually operates. These won't be as loud as something like your transmission failing, but they will definitely be some kind of whirring or grinding noise that you are not used to. if the noise gets continually louder, then you're likely closer to the problem getting worse and the actuator failing completely.
Slow Locking and Unlocking
A power door lock should work almost instantly when you press the button. A simple click in the door is unlocked or locked and you can go about your business. However, depending on how the actuator is failing it's possible that when you press a button to lock or unlock your door it will begin to work but it will struggle so much that it actually takes a moment for the locking mechanism to engage.
The most obvious sign that there's a problem with your door actuator is that the locks just don't work at all. You'll know this is an actuator problem rather than something else if the electrical systems in your car still work and you're still able to unlock the door with a key. One thing that's worth testing if you find yourself outside the car and you can't unlock it with your key fob is to ensure that the battery in your key fob has actually been replaced. Sometimes it's just a simple matter with that being the problem.
Normally it's not too much of an issue to use your key to unlock the door in your vehicle, but it's worth remembering that some vehicles don't actually have key locks anymore, in particular the newest model luxury cars. If that's the case, this problem we can be quite annoying to deal with.
Can I Fix My Own Door Actuator?
When it comes to repairing the door actuator you have the option of handling this job on your own. There are a number of handy guides online that can walk you through the process and you can actually get this job done fairly quickly and for much cheaper than a mechanic might charge you as well. A video like this one shows you a simple and easy way to get it done on the cheap, so you don't have to worry about investing a ton of money in it.
When you head to AutoZone you'll see that you can pick up a new actuator for as little as $30 though some of them get to over $200. It all depends on the make and model of your vehicle and you want to make sure you have the right one or you obviously won't be getting too far with it.
The main problem with fixing your own door actuator is properly diagnosing exactly what went wrong to cause the door to stop working in the first place. As we said you can be either mechanical issues or electrical issues that could have led to this problem. If it's a matter of a dead battery or a blown fuse then of course replacing the actuator itself isn't even necessary. But you have to know how to diagnose the problem first of all before you need to worry about exactly how you're going to get it repaired.
This would be the biggest problem for a DIY repair job if you're not well-versed in car repairs and figuring out exactly what went wrong. If you're not able to determine whether it was a mechanical or an electrical issue with your vehicle's door actuator that you may have to take it to a mechanic regardless because there's no sense trying to fix something if it's not broken, or investing time and money in something when there is another problem elsewhere in the vehicle that needs to be dealt with, right?
One of the other problems with doing a DIY door actuator repair is that many actuators were not built in a way that lends themselves to actual repair. Replacement is obviously very easy, but if you want to open up the actuator itself and get its side it can be a bit of a laborious task. Sometimes they seem to be designed with the idea in mind that repair was not going to be a possibility. They're often sealed with those plastic tabs that you have to use a screwdriver to pry them apart so that they slip out and will often break when you try to open them up.
Just as with pulling the panels off your door, if you're going to be conducting a DIY repair on the actuator just make sure you're taking your time and doing it as carefully as you can. A lot of these videos that show you what to do are made by mechanics who have a lot of experience doing this kind of work and they make it look very easy because they've done it a few times before. If it's your first time you may break those plastic tabs or feel like you're going to cause damage to your door other parts.
The Bottom Line
As we've said, a door actuator is not generally integral to the operation of your vehicle. You can get along just fine without one in most models, but it's going to be annoying to do so if you are accustomed to power door locks as most of us are. It may just be an inconvenience, but since your car is an investment that you've likely sunk a lot of money into there's no reason to have parts of it that don't work properly.
The thing you need to keep in mind is that a dealership is going to charge you a lot more than a mechanic to get this fixed typically. As well, the possibility does exist for you to buy some aftermarket parts on AutoZone and get it fixed yourself if you're comfortable doing this kind of work. It can save you a lot of money in the long run and get you back to having a fully functioning vehicle like you expect again. Whether you choose to take it to a mechanic or do it yourself, just make sure you're getting the exact right part for your vehicle.
The actuator assembly and position can vary greatly from one vehicle to the next and the job may be much more difficult to pull off in one model of a car versus another. If you do plan to do this job yourself make sure you research it ahead of time so you know what's going on otherwise heading to a mechanic is probably the best option you're going to have for getting this done and giving your doors back in good working order again as soon as possible.