Why is my lock not unlocking?

Most lock-unlocking issues boil down to a few practical causes: wear on keys or internal components, misalignment between the door and frame, dirt or corrosion in the mechanism, or a dead battery in electronic models. This guide outlines common problems and safe steps to diagnose them, plus guidance on when to call a professional.

Common causes of a lock that won't unlock

Traditional mechanical locks

These locks rely on a clean, properly aligned mechanism. When something goes wrong, the bolt may not retract or the key may not turn.

• Key worn or incorrect key: A worn key or the wrong key may fail to engagement internal pins or levers.


• Cylinder jam or stiff core: Dirt, rust, or dried lubricant can bind the cylinder, preventing turning.


• Stuck latch or misaligned strike plate: The bolt may not retract if the strike plate isn’t aligned with the bolt or the door is warped.


• Broken internal components: A broken spring, pin, or other part inside the lock can stop the mechanism from working.

Many traditional lock problems improve with gentle wiggling, proper lubrication, or realigning the strike plate. If issues persist or you hear grinding or scraping, a locksmith is the prudent next step to avoid damaging the door or lock.

Electronic or smart locks

Electronic models introduce power and software considerations that can complicate unlocking, even when the physical bolt appears fine.

• Dead or weak battery: Low power can prevent the lock from actuating or communicating with the app.


• Lockout, pairing, or firmware issues: Some models require re-authentication, app re-pairing, or updates after a reboot.


• Mechanical override not functioning: Some units have a physical key override that may also require attention if stuck.


• Moisture, temperature, or electronics fault: Extreme conditions can affect sensors or circuits.

Smart-lock problems are frequently resolved by replacing batteries, rebooting the device, or re-pairing with the app. If these steps fail, consult the manufacturer’s support or a professional installer to avoid compromising security or warranty.

Practical at-home troubleshooting

These at-home steps are designed to help you diagnose without causing damage. Start with quick checks and move to deeper steps as needed.

1. Check door alignment and strike plate: Inspect the gaps around the door and ensure the strike plate is properly aligned with the bolt; tighten hinges or reposition the strike plate if necessary.


2. Lubricate the mechanism correctly: Use a graphite powder or a silicone-based lubricant in the keyway or cylinder. Avoid petroleum-based oils that attract dirt. Insert the key and gently work it to distribute the lubricant.


3. Test with a spare key or code: If you have a spare key or a keypad code, try it to rule out key wear or code-entry issues; inspect for bent keys or worn codes.


4. Replace batteries and reset (if applicable): For smart locks, install fresh batteries, look for indicator LEDs, and follow the manufacturer’s reset procedure if the reboot option exists.


5. Gently re-check mechanical components: For a loose or stiff knob/lever, turn the handle while applying light pressure on the key or bolt to determine if there is still interior binding.

Proceed with caution: avoid forcing the key, bolt, or handle, as forcing can cause cosmetic or structural damage and may void warranties.

When to seek professional help

• You are completely locked out and cannot enter the property, even with spare keys or overrides.


• A key breaks off inside the cylinder or the lock shows visible damage or excessive corrosion.


• The door is misaligned beyond simple adjustment, or the frame is warped, making entry unsafe or impossible.


• Smart-lock issues persist after battery replacement, resets, and re-pairing attempts, or you suspect a security issue.


• There is any sign of tampering or a possible security breach.

When choosing a locksmith, verify licensing and insurance, ask for upfront pricing, and request a written receipt. For urgent lockouts, consider an emergency service with clear terms to avoid surprises. If you fear immediate danger or a security breach, contact local authorities.

Summary

Across traditional and smart locks, the core reasons for failing to unlock fall into wear and misalignment, dirt or corrosion, and power or software faults in electronic models. Start with quick checks: ensure door alignment, lubricate lightly with graphite, verify keys or codes, and replace smart-lock batteries. If problems persist, avoid forcing the lock and call a trained locksmith or the manufacturer’s support line when appropriate. With careful diagnosis and timely maintenance, most locking issues can be resolved without damage—preserving security and peace of mind.

How do you fix a door lock that won't unlock?

Loosen the screws, realign the lock parts, and slightly tighten it up, checking that the lock still rolls smoothly through its action. Tighten the screws some more, check, repeat until the lockset is firm and moving smoothly. I also have a tube of ``lock ease'' or similar silicone graphite lock lubricant.

What to do if the lock is not opening?

If a lock is not opening, first try lubricating it with a graphite or silicone-based spray to loosen the mechanism, then gently wiggle the key. If that fails, check if the door is misaligned, which can put pressure on the lock, and consider cleaning the lock mechanism or adjusting the strike plate. If the problem persists, you may need to call a professional locksmith for a more in-depth repair or to replace the lock. 
Immediate solutions

• Lubricate the lock: Spray a graphite or silicone-based lubricant into the keyhole. Avoid oil-based lubricants, as they can attract dirt. 
• Work the key: Gently insert and remove the key several times to distribute the lubricant. Wiggling or jiggling the key while turning it can also help, but be careful not to break the key. 
• Clean the lock: Use compressed air to blow out any dirt or debris from the keyhole. You can also use a thin tool like a toothpick or a straightened paperclip to carefully remove any visible blockages. 
• Address door alignment: If the door is sagging or misaligned, it can put pressure on the lock. Try pressing on the door while turning the key to see if it's the issue. 
• Heat the key (in cold weather): If the lock is frozen from cold, carefully warm the key with boiling water or a lighter to thaw the mechanism before inserting it. 

This video shows how to lubricate a lock to fix a stiff door lock: 58sMr. LocksmithYouTube · May 22, 2024
When to call a professional

• If the lock still won't open: If the above steps don't work, the lock may have a more significant internal problem, such as worn-out parts. 
• If the key is broken in the lock: A locksmith has the proper tools to extract the broken piece and repair or replace the lock. 
• If the problem is with the strike plate or door: A locksmith can properly adjust or replace the strike plate to ensure the door and lock align correctly. 

You can watch this video to learn how to fix a stuck lock with a key: 46sHome in PlaceYouTube · Sep 25, 2022

Why did my lock suddenly stop working?

Lock is either wearing out or needs to be lubricated. Lube it (cheapest and easy to do yourself - just have paper towels or a rag handy to catch drips) or replace it (fairly inexpensive if you can read up and do it yourself).