Keys that will not turn: causes and first steps

The most important rule when a key will not turn is to avoid forcing it. Keys are made of soft brass or nickel silver, and the cuts that matter are very small. Leaning on a key with a pair of pliers, or turning hard with the whole hand, is how a key snaps and leaves a broken piece inside the lock. That turns a small problem into a larger one.

Take a moment to notice what is happening. Does the key go all the way in? Does it turn slightly and stop, or not move at all? Does it work in the other lock on the same ring? Is it a front door, a car door or a padlock? These small observations narrow the cause, and they are exactly the questions a dispatcher would ask if you called.

Weather and time pressure make people hurry. If you are standing outside in the rain or the cold, it is natural to want to force things. If anyone is in danger, such as a child or pet shut in a car or someone who needs help inside, call emergency services first. Otherwise, a few slow checks are worth the time.

Think of it the way a dispatcher would. Before sending a crew, the first job is to understand what is happening. So gather facts. What kind of lock is it? When did it last work normally? Did anything change, such as a storm, a repair, a new key, a visitor or a door that was slammed? Often the answer to the last question points straight at the cause.

Look at the key. A key that has been used for years has worn cuts that no longer lift the pins to the right height. Keys also get bent when they sit in a back pocket or are used as a pry tool. A key that is slightly bent can slide in but fail to turn.

Check for dirt and lint on the blade. Pocket lint packed into the grooves can change how the key seats. A gentle wipe with a clean cloth is harmless. Then compare the key to a spare. If the spare turns smoothly and the main key does not, the main key is worn or bent, and a new one cut from the code or from the spare will likely solve the problem.

Beware of copies of copies. Duplicate keys are cut by tracing an existing key, and small errors multiply with each generation. A third generation copy may look right and still not lift every pin properly. Our notes on what happens when a key wears down and why duplicate keys sometimes fail explain this in detail.

Look for a worn shoulder or a rounded tip, too. The shoulder of a key is the step that stops it at the right depth. If it is worn, the key may sit slightly too deep or too shallow, and the pins end up at the wrong height. The tip can wear in the same way. A fresh key cut from the original code, rather than traced from a worn copy, often cures a lock that has seemed difficult for months.

Be gentle when you straighten a bent key. Bending it back by hand can weaken the metal and invite a break. If the key is only slightly bent, it is safer to replace it than to coax it into shape. Keys cost little compared with the cost of removing a broken piece from a lock.

If the key is good, the lock is next. Inside the cylinder, tiny pins and springs sit in a row. Dust, grit, rust or old grease can jam them. In the valley around Redding, fine summer dust works its way into outdoor locks. In the mountain towns, moisture can freeze and hold the pins in place.

Pins can also wear or stick for mechanical reasons. A cylinder that has seen heavy use for many seasons may have worn pins and springs that no longer move freely. In that case the key goes in but the pins do not rise to the proper height. The lock feels gritty or inconsistent: sometimes it works, sometimes it doesn't.

One more cause is a cylinder that has been tampered with or forced in the past. If a lock has been picked clumsily, hit or drilled, the internal parts may be damaged. A professional can inspect the cylinder, clean it, or replace it, as needed.

Cylinders also fail from the inside out. A cracked spring, a pin that has slipped out of place, or a part that has worn through can leave the lock feeling loose, then stuck, then dead. These problems rarely fix themselves. When a lock that was fine last week suddenly will not turn at all, it is often a broken internal part, and the right step is to stop using it and have it inspected.

Aftermarket or very inexpensive cylinders, especially older ones, sometimes use softer metals that wear sooner. A lock that has served a busy door for many seasons may simply be tired. In that case, a replacement cylinder or lock is a better investment than another round of cleaning and lubricant.

Sometimes the lock is perfectly fine, and the door is the problem. If the bolt is under pressure from a misaligned door, the key cannot turn because the bolt is jammed against the edge of the strike. You may notice that the key turns easily when the door is open but not when the door is closed.

Try this gentle test. With the door closed, push in or pull out slightly on the door while you turn the key. If it suddenly turns, the door and frame are not lined up. Houses settle, hinges loosen and wood swells, and that shifts the bolt away from its hole.

Long term, that kind of pressure wears out the lock. The fix is alignment: tightening hinge screws, adjusting the strike, or filing the opening. We describe how that works in our guide on doors that do not latch. If you suspect alignment, a locksmith can sort it out without replacing a good lock.

Another test is to look at the bolt itself. Turn the thumb turn on the inside with the door open. If the bolt moves freely when the door is open and sticks when the door is closed, you have confirmed a contact problem between bolt and strike. If the bolt is slow or sticks even with the door open, the problem is inside the lock body.

Remember that a lock which is being forced against its strike every day wears out sooner. Spending an hour on alignment can add years to the life of a lock. This is one reason we like to look at the door whenever we are called to a stubborn lock, not only at the cylinder.

• Test whether the key turns easily with the door open.
• Press or lift the door gently while turning the key and see if it frees up.
• Look for a bolt that rubs on the edge of the strike.
• Check that hinge screws are tight and the door is not sagging.

From Mount Shasta to Weed to Yreka, cold mornings bring a particular set of lock problems. Moisture inside a lock can freeze and hold the pins still. A key goes in and meets resistance. Forcing it can break the key.

Safe first steps are gentle. Warm the key in your hands, or hold it in your fist, and try again. Use a lock de icer made for the purpose if you have one, and avoid pouring hot water, which can refreeze and make the problem worse. Avoid using flames near a lock or near a vehicle.

We have written more about this in winter lockouts and frozen locks in the mountains and about the related problem in a deadbolt that sticks only in the cold. Prevention is mostly about keeping water out and using the right lubricant.

If you live where cold snaps are common, treat the lock before the freeze. Wipe moisture from the keyway, use a lubricant meant for locks, and keep the cover on any exposed padlock. A small amount of prevention takes the edge off a cold morning, and it protects keys from the strain that comes with a frozen lock.

Hot weather causes its own trouble. Metal expands, door frames swell with humidity, and lubricants thin and attract dust. A lock that works in the morning can stick in the afternoon because the door has shifted slightly in the heat.

If a key only sticks at certain times of day, suspect temperature and alignment. Try the key at a cooler hour, or ease the door by lifting while you turn. If this helps, the lock needs attention to the door, not the cylinder.

Dust is a quiet culprit in dry months. It mixes with oil to form a paste in the keyway. A blast of dry graphite based lock powder, or a spray made for locks, may loosen it. Avoid thick oils and general purpose sprays, which hold dirt. Our piece on lock lubricants goes through the options.

Dust and grit also come from the keys themselves. A key that rides in a pocket with coins, a pocketknife and lint carries debris into the keyway every time. Cleaning the key with a cloth now and then is a simple habit that keeps the lock clean as well.

If the key will not turn in a vehicle, the cause may not be the lock. A steering wheel that is locked tight can bind the ignition so the key will not rotate. Gently turning the wheel back and forth while you turn the key often releases it. Do not force the key.

Worn ignition cylinders and worn keys are common on older vehicles. If your key has a rubber or plastic head with a chip inside, it is a transponder key, and the car also needs to recognize the chip. A key that turns but fails to start the car is a different problem from one that will not turn at all.

For more detail, see our notes on ignition trouble signs and why a steering wheel lock sticks. If the ignition is worn, an automotive locksmith can often service or replace it without replacing the whole column.

For door locks on vehicles, a key that turns freely but does not unlock the door may point to a worn actuator rather than the key. If the key will not go in at all, or turns only part way, look for a damaged key or a lock that has been forced. Vehicles also use a mix of key types, and some modern keys depend on a chip, so a key that turns but does not start the car is a different story. For key types and what they mean, see car key types in plain words.

Avoid hammering, bending or prying. Avoid using a wrench or pliers on the key. Avoid spraying heavy oil or thick grease into the lock. Avoid trying many different keys in a row, since each insertion can push grit deeper or scrape the pins.

Avoid drilling the lock yourself. Once a lock is drilled, it almost always needs to be replaced, and a drill can damage the door. Avoid dropping the key into the lock with hot water or flames. These ideas show up online and tend to create bigger and more expensive problems.

Finally, avoid ignoring the problem. A lock that is getting harder to turn is warning you. Doing nothing leads to the day it fails completely, usually at the worst moment. Addressing it early with cleaning, lubrication or a new key usually costs far less than waiting for a lockout.

It is tempting to try every trick that comes up in a search. Resist that urge. Some online advice, such as tapping on the key with a hammer, is more likely to cause damage than to help. A lock is a precision instrument, and the pins inside are tiny. Patience and a light touch cost nothing and save a lot.

Here is a sequence to try, in order. First, make sure you are using the right key, and compare it to a spare. Second, inspect the key for bends or heavy wear. Third, check whether the door is under pressure, by pushing or lifting while you turn. Fourth, consider weather and gently warm or clean the lock if appropriate.

If none of that helps, stop. Do not escalate to force. At this point, the cause is likely inside the cylinder or in the door and frame alignment, and each of those is a job for a professional with the right tools.

Describe exactly what you did and saw when you ask for help. That saves time. Our lock repair and house lockout pages describe what we can do on site.

Write down the order you tried things in. If you do need a locksmith, that list is useful. It tells us what has already been disturbed, and it keeps us from repeating steps. It also helps you notice patterns, such as a lock that only fails when the weather turns, or only after a certain person has used it.

Finally, think about the next time. A spare key stored safely, kept away from the main ring, can bring a stuck lock under control. Our guide on storing spare keys safely covers where to keep one, and how to keep it from being a risk.

A locksmith can test the cylinder, clean it, replace worn pins, or recommend a new lock when repair is not worth it. For a car, we can service ignition and door locks and cut or program new keys. For a business, we can check commercial hardware and closers.

Tell us the type of lock, the age of the key, the weather conditions and what you have already tried. A photo of the lock and the key is helpful. Please do not send personal details beyond what is needed to arrange the visit.

The phone line is coming soon. Right now the way to reach our crew is the request form. If the situation is urgent or unsafe, contact emergency services. We cover communities from Redding and Anderson to Weed and Yreka.