Car Key & Fob Programming

Get a spare before you need one

Adding a key while you still have a working one is straightforward on most cars. Replacing the only key after it is lost can be a much bigger job, and on some makes it means removing a module or working through the manufacturer’s security process. If you are down to one key, a spare is the cheapest insurance you can buy for the car.

When the car won’t recognize the key

If the car cranks but won’t start, the security light flashes, or the dash says the key isn’t detected, start with the simple things: a weak fob battery is the most common cause, and many cars let you start with a dead fob held against a marked spot on the steering column or console. If a fresh battery doesn’t fix it, the fault can be the key itself, the antenna or receiver that reads it, or the immobilizer data in a module. We test those in order rather than selling a new key first.

A weak 12-volt battery causes immobilizer and “key not detected” messages too — see battery, alternator & starter repair.

European, luxury and older cars

Keys on BMW, Mercedes-Benz, Audi, VW, Volvo and other European cars are tied closely to the car’s modules, and some makes only allow keys to be added through the manufacturer’s own security system. We run the factory software for those makes (see our ECU programming) and will tell you honestly when a key has to come from the dealer. Older cars with a separate immobilizer box or a failed module are often where an independent shop saves the most, because the alternative is replacing modules the car doesn’t need.

Key programming in Worcester

We’re at 209 Stafford St, Worcester. Every car is different, so call or book with the year, make and model, and whether you still have a working key. We’ll confirm what the job involves and quote it before you come in.