
Car keys · Cambridge
Car Key Replacement
The engine cranks, catches for a second and dies, and a small key-shaped light keeps blinking on the dash. The blade turns the ignition and the doors perfectly well, but the car has stopped recognizing the chip inside the key.
Car Key Replacement
In plain words
Winter produces its own kind of key trouble. Coin cells lose output in deep cold, so a fob that was fine in October goes quiet in January; a fob dropped in slush or lost under a snowbank is gone until spring; and the mechanical door lock on a keyless car, untouched for years and crusted with road salt, is stiff exactly when you need it. A replacement visit in these conditions covers it all: a working fob, fresh batteries, a cut emergency blade, and a door cylinder cleaned and lubricated per the maker's instructions, so the metal key is a real backup rather than a decoration.
How the visit goesYou bought the car privately and it came with a single key on a shoelace. Every time it leaves your hand you notice, and you would like a second one made before the first goes missing.
Cambridge
How the visit goes
The car itself: battery, access and location
Programming writes to the vehicle's computers, so the locksmith checks the basics of the car before starting. A weak battery from a car that has sat locked for weeks is put on a maintainer so the voltage stays steady through the session. The diagnostic port under the dash has to be reachable, which means the car has to be opened first if every key is gone. Where the car is parked matters as well: an underground garage with poor light, a tight street spot or a snowbank against the driver's door all shape how the work is set up. A few questions on the phone cover most of this.
Pairing the remote and the proximity fob
The buttons on a key and the transponder in it are usually separate systems, and the remote is paired in its own step. Depending on the vehicle, that is an on-board routine of ignition cycles and button presses, or a command sent through the programming tool. A proximity fob is registered so the car detects it near the door handles and inside the cabin, and push-button start is tested with the fob in a pocket, then held against the start button as the backup method. Remote start, trunk release and panic are checked one at a time, since a wrong part number can pass every step except the one you use most.
Looking after the mechanical lock you rarely use
On a keyless car the door cylinder can go years without a key in it, which is exactly why it seizes with salt and grit. After the visit, use the emergency blade in the driver's door once a season so the wafers keep moving, and follow the vehicle or lock maker's own maintenance instructions once the salt is off the roads in spring, since automotive locks more often need cleaning than added lubricant. In a cold snap, a small tube of lock de-icer in a coat pocket does the job; hot water only refreezes inside. A lock that has been freed during the visit stays free with this little attention.
Car Key Replacement
In the van
- Remote frequency tester
- Laser-style milling cutter
- Transponder chip
- OBD programming tool
- Remote-head key shell
What affects the quote
Same fees day, night or weekend
1How many keys you leave with
Each key is a blank, a cut and a programming slot, so the total follows the count. Making the spare during the same visit is usually the sensible time to do it.
2Original or aftermarket part
A manufacturer fob and a good aftermarket equivalent both do the job on many models, at different part costs. The locksmith says which is proposed for your car and why, and the quote names the part.
3Shell only, or a complete key
If your key's electronics are healthy, a new case and blade around the old board is a smaller job than a complete key with programming. The inspection decides which, before anything is quoted.
Car Key Replacement: questions
Can a key be made for an older car with no chip?
Yes, for a vehicle that genuinely has no immobilizer, checked by VIN and equipment rather than assumed from age, since several early-2000s vehicles already shipped with a factory immobilizer and coded key. Where that is the case, it is the simplest key work there is: a blade cut to the factory code from the VIN or to a reading of the door lock, rather than copied from a worn original. If the ignition has become sloppy, the locksmith can rebuild it in the same visit.
My fob is cracked but still works. Do I need a whole new key?
Usually not. A cracked case often protects a healthy circuit board and transponder, and those can be moved into a new shell of the same pattern with a freshly cut blade. Because the electronics are unchanged, nothing needs programming, and the rebuilt key behaves exactly as before. A new key is the answer when the board is corroded, a button has died or the chip has been damaged.
Does programming a new key affect the keys I already have?
Adding a key leaves the existing keys in place; the car simply learns one more. The exception is a deliberate all-keys-lost reset or an erase you ask for, which clears every stored key and then registers only the ones you present. For that reason the locksmith asks you to bring every key you own to the visit, so each one can be re-registered and tested rather than left behind and forgotten by the car.
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Car Key Replacement near you
One team handles every service on this page for Cambridge, so a lockout can turn into a rekey, and a rekey into a properly set deadbolt, within the same visit if you want it. Each service is described separately below, but at the door they fit together as one piece of work.