uk Transport & mobility emergencies cracked car key • damaged car key • broken key fob • smart key cracked • key casing split • key may fail soon • car key falling apart • key fob damage • remote key damaged • key blade loose • push button start key issue • keyless entry problems • spare key missing worry • only car key damaged • car won’t start risk • worried about being stranded • key fob battery cover broken • key stopped working intermittently • car key dropped and cracked

What to do if…
your key or smart key is cracked or damaged and you worry it may fail before you get help

Short answer

Stop relying on the damaged key as your “only way home”: switch to a spare key if you have one, and book a replacement/programming route now before the damaged key fully fails.

Do not do these things

Don’t keep “testing it” over and over (repeated lock/unlock/start cycles can be the moment it finally fails).
Don’t pry the casing open further or glue it shut unless you’re sure you won’t trap buttons/battery contacts (you can make it worse fast).
Don’t leave the cracked smart key in rain, pockets with coins/keys, or anywhere it can be bent or crushed.
Don’t assume a newly cut blade alone will solve it (many modern keys also have a transponder chip/fob that must match the car).
Don’t post photos of your key (cuts/shape and identifiers can be misused).

What to do now

If you have a spare key, switch to it immediately. Put the damaged key somewhere safe and dry (at home, in a drawer), not on your daily keyring.
If you don’t have a spare, reduce “start risk” today.
- Combine errands into one trip (fewer restarts).
- Avoid turning the car off/on unnecessarily in awkward situations where a no-start would be especially stressful (e.g., tight ramps, ferry queues, remote car parks).
- If you need fuel, still turn the engine off for refuelling—just plan so you’re not doing multiple short stops.
Do a quick check of your vehicle’s backup entry/start method (model-specific). Many key fobs have a hidden mechanical key blade for the door, and many keyless-start cars have a backup way to start if the fob is weak. Check your owner’s manual/app so you know the exact method for your model.
Stabilise the damaged key to buy time (temporary, gentle).
- Put it in a snug protective cover/case if you have one, or wrap the cracked area with a small amount of tape to stop it spreading.
- Keep it dry and avoid pressure on the cracked section.
- If the battery cover is loose, secure it so the battery can’t lift or lose contact.
Book a proper replacement route today (choose one):
- Dealer/manufacturer service (often most straightforward for modern smart keys).
- A reputable auto locksmith who can cut and program the correct type of key/fob. If you’re choosing a locksmith, look for one that’s Master Locksmiths Association (MLA) approved and explicitly offers automotive keys, or otherwise clearly demonstrates automotive key programming capability.
Prepare what they’ll ask for so you don’t lose time under stress: photo ID, vehicle location, make/model/year, and the VIN (often visible at the base of the windscreen). If you have it, keep your V5C details handy too.
If you’re at risk of being stranded (no spare + key is intermittently failing), line up “rescue cover” now. Check your breakdown cover/insurance for key assistance options and save the relevant phone number.

What can wait

You don’t need to decide today whether to buy an “extra” third key, change locks, or upgrade security hardware.
You don’t need to troubleshoot every possible cause (water damage, battery, contacts) right now—your goal is simply to avoid total failure and get a working replacement arranged.
You don’t need to settle the cheapest long-term option this minute; first secure a reliable way to start/unlock the car.

Important reassurance

It’s very common for cracked fobs to work “just enough” until they suddenly don’t. Taking a few calm steps now (spare key, fewer cycles, booking help) usually prevents a stressful lockout or being stranded.

Scope note

This is first-steps guidance to reduce the chance of sudden key failure and get you to the point of arranging a proper replacement. Vehicle-specific details (especially for keyless start) must come from your manual for your exact model.

Important note

This is general information, not mechanical or legal advice. If you feel unsafe where you are, prioritise getting to a safer location and contacting breakdown support.

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What to do if…your key or smart key is cracked or damaged and you worry it may fail before you get help