Frozen or seized car lock in Halifax: what to do after freezing rain

Have I tried every door and the hatch?

Start there, every time. Ice and wet snow rarely coat a car evenly. The side that faced the wind or the slush from passing traffic takes the worst of it, and the far door or the hatch may open without a fight. AAA's first tip for a frozen lock is the same: if the fob isn't helping, try the locks on your other doors (AAA via 6abc).

Once you are inside through any door, start the engine and run the heat. A stuck door often lets go from the inside within a few minutes as the cabin warms.

The car is glazed in ice from freezing rain

Freezing rain leaves a hard, clear shell over the whole car, sealing door seams, handles and keyholes at once. Don't attack it with a scraper edge, a key or anything metal near the paint and the lock.

• Crack the glaze with pressure. Press the heel of your hand firmly along the door seam and around the handle. The thin shell usually breaks along the gap.
• Clear the keyhole cover. Many cars have a small cap over the driver's lock. Ease ice off it with a plastic scraper rather than prying.
• Use de-icer on the lock, not the whole door. Spray into the keyhole and wait before trying the key.

If the shell is thick and every door is sealed, patience and a remote starter (if you have one) do more than force.

Why is hot water a bad idea?

Pouring hot water is the trick everyone has heard of, and it backfires. AAA says plainly never to pour hot or boiling water on your car, since it can crack the glass. And when the glass survives, the water runs straight into the lock, the latch and the seals. After a freezing rain storm, with more cold on the way, it sets again within minutes, deeper inside the lock than before.

Lock de-icer is the right tool. It melts ice inside the cylinder and evaporates instead of freezing again. Squirt it in, give it a moment, then try the key with gentle pressure.

Where you keep it matters. CAA's winter kit advice is to carry lock de-icer on you rather than leaving it in the vehicle (CAA emergency kit). A can in the glovebox can't help when the door won't open.

Out of de-icer? What works from a coat pocket

Hand sanitizer is the stopgap most people are carrying. AAA suggests a little hand sanitizer or isopropyl alcohol on the key so it slides in, then turning gently. The alcohol lowers the freezing point of the ice it touches.

You can also warm the key:

• Hold the metal blade in your gloved hand for a minute, or warm it with your breath through cupped hands.
• Keep heat away from the plastic head. It may hold a transponder chip or a remote, and melting it adds a second problem.
• Never bring a lighter or any flame near de-icer. Most contain alcohol and burn easily.

Push the warm key in, wait a few seconds, and turn lightly. Repeat a few times rather than leaning on it.

Is it ice or salt corrosion?

Two different problems can feel the same at the door.

Salt spray from the roads and the sea air near the harbour corrode exposed metal, and a door cylinder that only gets used when the fob dies is the one most likely to seize. De-icer does nothing for corrosion. Forcing a seized cylinder is the most common way keys snap.

Key turns, door stays shut

If the key turns but the door won't move, the lock has done its job. Water has frozen the rubber seal to the frame, and hauling on the handle can tear the seal or break the handle.

Try this:

1. Lean into the door and press firmly all around the edge to break the ice bond.
2. Pull the handle and hold it out while you rock the door gently in and out.
3. If that fails, get in another door, start the car and let the heat loosen the seal.

If the handle goes slack or springy and doesn't return, leave it alone. A broken latch rod inside the door is a far bigger job than ten minutes of waiting.

What if the key starts to bend?

Stop turning. A frozen or corroded lock is an inconvenience. A key broken off in the cylinder is a repair: de-icer can't reach past it, the broken piece has to be extracted, and you may need a new key cut. Car keys are softer than they look, and a cold key twisting in a stuck cylinder can give way sooner than you expect.

A visible twist in the blade is your warning. Switch to de-icer or make the call.

How do I stop freeze-thaw and salt seizing my locks?

A few habits prevent most stuck mornings on the coast:

If you depend on the fob, know what to do when it acts up in the cold and damp. That is covered in key fob not working in cold weather.

On remote starters: they help on an iced-up morning, but never leave the only key inside a running car, and never remote-start a car in a closed garage. Health Canada advises against idling a vehicle in the garage even with the door open, because carbon monoxide can build up and seep into the house (Health Canada). If a child or pet is locked inside a car, call 911 first.

When is it time to call a locksmith?

Call once you have tried the other doors, de-icer and a warmed key, and the next step would be force. That is when a stuck lock becomes a broken one. Call as well if:

• the key has bent or broken off in the lock,
• the lock is seized and won't turn even on a mild day,
• the keys are locked inside the car,
• a door was forced and now won't latch or lock.

A locksmith has tools for opening a car without prying at the door, and can extract a broken key or deal with a cylinder that has stopped working. If you are locked out right now, go to car lockout help.

If it is your garage door that has frozen to the slab, the causes and fixes are different: see garage door won't open in cold weather. And if the key itself is gone, read can a locksmith make a car key without the original.