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7 Reasons Why Your Manual Key Won’t Unlock the Car Door

Imagine being late to a meeting or for class only to find out you’re doomed because your car won’t unlock with the key or fob. Here are seven potential causes why your key can’t open the door.

The Lock Tailpiece Is Broken

Several locking mechanisms use the same principles. Similar to the conventional door lock, most car locks also have a tailpiece that can get damaged over time.

The lock tailpiece connects the key to the lock latch or bolt. This is usually found in locks that have a lazy cam. The tailpiece moves approximately 90 degrees around its attachment point to move the cam and linkage. It also brings the key back to the key-pull position without altering the latch settings.

The Lock Cylinder Is Damaged

After some time, dirt and corrosion could damage the parts of the door lock cylinder, which could explain why the manual key can’t unlock the door.

After some time, dirt and corrosion could damage the parts of the door lock cylinder, which could explain why the manual key can’t unlock the door. A typical car door lock cylinder is composed of the keyway, cylinder housing, plug, tumblers and pins, and springs.

The cylinder’s tumblers are most prone to damage. These are the small brass plates that can be found in the cylinder core. These plates line up with the cuts in the keys, turning the cylinder and unlocking the car door in the process.

The Key Is Worn-Out

A worn-out key will prevent the tumblers from lining up, keeping the entire lock from rotating. Your key is bound to wear out after using it multiple times, so it’s best to make a copy while it’s still in good condition. A duplicate of the worn-out key will also be unable to open the car door.

The Key Hole Is Contaminated

Dirt can build up inside the keyhole and make it hard for you to open the door. The keyhole can also wear out after sliding the key in and out multiple times.

In some cases, lubricating the keyhole can resolve the problem, but keep in mind that it’ll only be a temporary fix. Eventually, you’ll need to replace the entire lock.

The Car Lock Needs Lubricant

A typical car lock rarely needs oil, but repeated use can cause its metal parts to wear out or get stuck, so you’ll need to apply oil once it gets difficult to turn the key.

To resolve this issue, you can try pouring oil onto the grooves of the key before sliding it into the lock. Essentially, you’ll be using the key to spread the lubricant inside the locking mechanism. Be careful about using too much oil because dirt and other contaminants can get stuck, which can make it even harder to unlock the car door.

The Lock Is Frozen

Drivers who live in areas that have freezing temperatures are most likely to deal with a frozen lock. Fortunately, it only takes a de-icer spray to resolve this problem, and your lock will be as good as new.

The Door Latch Is Stuck

If the key and lock are working perfectly fine, chances are you might be dealing with a stuck door latch. Like most components, rust and corrosion can affect the door latch and prevent you from opening the door from the outside.

How to Unlock a Car Door Without a Key

A defective key or lock can be frustrating to deal with, especially when you’re in a hurry. So what can you do to get inside your car? Here are some DIY-friendly hacks you might want to check out.

Use a Slim Jim

A slim jim is a thin piece of metal rod that can slide between the window and weatherstrip to reach the lock cylinder and unlock the car door from the inside.

You’ll need to apply enough pressure until you feel resistance from the lock and hear a soft click.

Create Some Space Using an Inflatable Door Wedge

An inflatable door wedge is a rubber bag that creates a space between the door and the door frame without damaging the paint job. Once there’s enough space between the door and the frame, you can insert the necessary tools to unlock the door.

Pull the Lock With a Shoestring

This idea might sound simple, but it can be a lot harder than you think. This method involves creating a small loop in the middle of the shoestring and bringing it all the way down to the lock using a flossing motion.

Once the loop is placed on the lock, you’ll be able to tighten it by pulling the two ends and pulling the string upwards to unlock the door.

Use an App

A lot of modern cars come with keyless entry features, especially those from FordSubaruHyundaiNissan, and Chevrolet.

Various models from these brands can be controlled using smartphones when it comes to locking and unlocking the doors and starting the engine.

Call an Expert

If all the other methods fail, the last thing you can do is call an expert. It can even be the first thing you can do if you don’t want to go through the trouble of trying the previous DIY solutions. Locksmiths are trained professionals that can help you unlock your car door with minimal effort. Depending on the severity of the issue, a locksmith can charge anywhere between $50 and $250 for labor.

Meanwhile, drivers who are members of the American Automobile Association (AAA) can request roadside assistance for free.

Key Takeaways

Your car door’s locking mechanism is generally something that requires little to no maintenance, but keep in mind that it can still fail after a while. A contaminated or damaged lock and a worn-out key are some of the probable causes of a stuck door lock.

And while there are several Use an AppDIY methods you can try, nothing beats the expertise of a locksmith when it comes to unlocking doors.


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