How do I know if my car key has a transponder chip inside it?

Looks alone can't settle it. Some chips sit inside a metal-looking head, and some plastic-headed keys carry no chip. The vehicle's year, make and model give the firm answer, and a locksmith can confirm it before any work starts.

What the chip does

What you can check yourself

• Look at the head of the keyA thick plastic head, often with a seam or a rubber-like cover, is a strong hint that a chip is inside. A thin, all-metal key on an older car is less likely to have one.
• Watch the dashboardMany cars show a small key or lock-shaped light that blinks when the car is off or when the key is in the ignition. That light usually belongs to the immobiliser system, which means the key carries a chip.
• Check for buttons or push-to-startIf the key has lock and unlock buttons, or the car starts with a button and no key turns, the key almost certainly holds electronics that need programming.
• Read the owner's manualLook in the index for words like immobiliser, transponder or key programming. The manual often states which key type your vehicle uses and how many keys are registered.
• Have the vehicle details readyThe year, make and model, and the vehicle registration or insurance papers, help a locksmith identify the key type quickly.

What the locksmith will do

• Identify the key typeThe locksmith confirms the vehicle's year, make and model and works out whether it uses a chip key, a remote key or a push-to-start fob.
• Cut and program the keyThe key is cut to fit and the chip or fob is programmed at the vehicle so that it starts the car.
• Remove a lost key from the car's memoryWhere the car supports it, a lost key is cleared from the vehicle's memory so it can no longer be used. This matters most when a key was lost rather than broken.
• Test before leavingThe new key, and any spare, is tested on the vehicle before the locksmith leaves.

Related questions

Can any car key be programmed by a locksmith?

Not every vehicle can be keyed away from a dealer, so the make and model decide what is possible. The locksmith can tell you once the vehicle details are known, and the price is agreed before work begins.

If I lost the key, does the old one still work?

It can, unless it is removed from the car's memory. Where the vehicle supports it, the locksmith can clear the lost key so only the new keys start the car.

Is a key fob the same as a transponder key?

Not always. A transponder key has a chip that lets the engine start, while a fob mainly handles remote functions. Many modern keys combine both, and push-to-start fobs have to be paired with the car.

Will a plain cut key start a car that has a chip?

Generally not. A cut blade may fit the ignition, but if the chip hasn't been programmed to the vehicle the car will not start.

My key snapped. Is the chip damaged?

It depends on where the break is. Keep every piece and tell the locksmith, who can check what is left and what the vehicle needs.

Keep reading

• What's it doing?Lost car key or fob
• AnswerWhat does it mean when my new key turns but the engine won't start?
• AnswerWhy does the year make and model matter for replacing a lost car key?
• AnswerWhat proof of ownership will a locksmith ask for before cutting a car key?
• Every lock question we have answered