If you’re like most drivers, locking up your vehicle is second nature. Your car door locks help to keep your valuables safe and prevent any would-be thieves from taking your whip for a joy ride!
Despite all the security they provide, car door locks aren’t perfect. Like the locks on your front door at home, automobile locks can fail. If your key turns but won’t unlock the car door, you might end up stranded with no way to get inside.
So, why does key turns but won’t unlock car door issue occur? It turns out that there are several potential reasons why your car door lock might not work despite an operational key. Here are the most common causes and solutions to try out.
1. A Damaged Lock Tailpiece
The internal mechanisms of a car lock are more complex than most realize. Your car’s door is likely thicker than the doors you have at home. To compensate for that added width, automakers utilize a tailpiece. Also known as a turn piece, this component is responsible for triggering a lever within the door.
As you turn the key, the tailpiece should open the latch through a series of push-pull connections. We won’t get into the technical details here, but a damaged tailpiece will prevent the lock mechanism from functioning as it should.
Fixing this issue is best left to a professional. While the part itself is rudimentary, getting to it requires getting into the door. With actuators, window controls, and a host of other elements in the way, it’s better to let an expert take the reins.
2. A Faulty Lock Cylinder or Damaged Tumblers
Beyond the tailpiece, one of the most critical parts of your car door lock is the cylinder and the tumblers it houses. The cylinder is the tube-like section that holds your key when you insert it. While you can’t see what’s inside, most cylinders hold all of the tiny components like the actuator and plug.
More importantly, the cylinder also houses the tumblers that “read’ your car key and prevent random people from getting into your car. Most automobile locks these days use wafer tumblers.
If your key is turning but not unlocking the car, there’s a good chance that the cylinder and wafers aren’t working correctly. Manufacturers build car locks to withstand the elements and continual wear. However, they’re not indestructible.
Thanks to the intricate nature of these locks, even minor damage can prevent proper functionality. The issue could be bent metal after a physical accident. Alternatively, it can be something as simple as dirt and debris stuck inside the cylinder!
Whatever the case, repairing this issue requires disassembly and possible replacement.
3. Poor Lubrication
Has it been a while since you used your key? You’re not alone! These days, most vehicles have a wireless key FOB that locks and unlocks your car. It’s only when the FOB has dead or worn-out batteries that drivers typically start using the key.
But if it’s been months or years since doing so, don’t be surprised if the lock doesn’t respond straight away. Locks are intricate and have many moving parts. Constant exposure and a lack of movement will make those complex components pretty stiff.
Luckily, this issue is pretty easy to resolve with a little lubricant. Spray a bit of all-purpose industrial lubricant onto the grooves of your key. Don’t go overboard, as too much oil will attract dirt and exacerbate the problem. After a light spray, insert your key and turn the lock. Repeat this process several times to get things moving.
4. A Worn-Out Key
Here’s what happens when you have the opposite problem to routine key FOB usage. If you use the key regularly, it can wear out over time. Don’t let its robust metal construction fool you. Years of use will cause the grooves to become less defined, resulting in issues with the tumblers.
The tumblers have to line up perfectly to initiate the locking mechanism. Eventually, the grooves can get low enough to throw things off and stop proper functionality.
Your best bet here is to call a locksmith and have them cut a new key using the key code registered to your vehicle. Make sure they don’t simply duplicate your existing key, as that would only replicate the worn grooves. And if you have a transponder key, don’t forget to have them program the RFID chip inside.
5. Frozen Lock Mechanisms
When the winter season rolls around, you must do more than invest in snow tires to keep your car in good shape. Freezing temperatures can prevent your locks from working as they should.
There are a couple of techniques for battling ice and extreme temperatures. The first is to use a de-icing solution. Lock de-icers look like lubricants. They come in a spray bottle that you can apply to your key.
If you don’t have a de-icer on hand, you can always use a lighter. Use it to warm up the key and melt the ice. The key doesn’t have to be red-hot. Exercise caution and use your best judgment.
To prevent ice issues in the future, many car owners utilize a glycerine and water mixture. Combine two parts glycerine with one part distilled water. Then, apply it to your key and apply it to the lock’s internal components. The mixture has a low freezing point, ensuring that your mechanisms don’t ice over.
6. A Bad Actuator
This problem is less likely, but it can still occur. The actuator is the tiny motor inside your car door that handles the power locks. When using the FOB or pressing the buttons inside, the actuator triggers the mechanism to secure the door.
An actuator is responsible for power locking, so damage shouldn’t prevent manual usage. However, it can cause some erratic behavior. The lock might switch unpredictability. When you use the key for manual unlocking, you might also feel resistance and sluggish movement. If the action is so bad that the lock won’t open, it’s a good idea to get help from a locksmith or mechanic.
7. Deadlocks or Child Safety Locks
If your car key turns but won’t unlock the door, the culprit could be another locking mechanism. Many vehicles have deadlock systems to add another layer of security. These locks essentially disengage door handles, requiring you to take additional steps to get in.
That could be flipping a switch or turning the key farther than usual. Either way, the feature is easy to miss if you’re unaware that it exists.
One of the most prevalent types of deadlocks is a child lock system. They stop your young one from opening the door while you’re on the road.
Check the owner’s manual for information about deadlocks. Typically, fixing the issue is as simple as flipping a switch. For child locks, the control is usually on the side of the door. Once you disengage it, the mechanism should act normally.
8. A Stuck Latch
Last but not least, the issue could involve the latch itself. The latch is the mechanism that holds the door closed. It interacts with a U-shaped anchor in the door jamb.
Latches are relatively reliable, but they can bend with physical force. Rust and debris can affect functionality, too. Help from a mechanic is the best course of action. Don’t worry: Fixing or replacing the door latch is usually quick and affordable.
Car door lock issues can be a massive headache when you’re in a rush or anywhere but home. If you ever find yourself dealing with a lock that doesn’t work, consider these potential causes to figure out what’s happening. Most issues are easy to fix. Use our tips or contact a professional for help.
To avoid problems in the future, do your best to keep your locks in good shape. Lubricate them every once in a while and take measures to prevent damage and freezing. With just a few minutes for maintenance, you can rest assured that you’ll never be locked out!