Your key fob stopped working. Here's the order of things.

Fobs, remote-head keys and smart keys: how each is replaced without a dealership.

Three things in one small box

The fob does two jobs: it talks to the door locks over radio, and on push-start cars it carries the chip that lets the engine run. When it stops, it's almost always the battery, sometimes the buttons, and occasionally the car and fob have lost their pairing.

For most cars around Marlborough a locksmith does this where the car is parked, the same day.

The two-minute check

Start with the battery. Open the fob at its seam, read the cell type off the old one, buy the same. If the car is push-start and won't see the fob, hold the fob against the marked spot on the column or console and it will start. A fresh battery ends most fob stories.

New battery and still nothing, or no fob at all: that's when the locksmith comes in.

Making one from nothing

All fobs gone: the locksmith works from the car. Ownership is checked, a new fob is programmed to the vehicle, and the missing fob is deleted from the car so it's useless to whoever finds it.

Proof of ownership first, without exception. Then the work.

One fob is a bad number

With a working fob in hand, a spare is fast. The car accepts a second fob next to the first. Without one, the car has to be read and the job grows. If your Marlborough household is sharing one fob, this is the moment.

Same visit, same equipment: adding a spare when the locksmith is already there is the efficient way.

Which one is yours

Three types: the key with buttons in its head, the separate fob and plain key, and the bladeless smart key. Each pairs to the car differently and a mobile locksmith carries the equipment for all of them. Smart keys take longest.

Year, model, and a picture of the fob: that's all the technician needs to bring the right part.

Things people are told

You have to go to the dealership. Usually not. The car has to be moved. It doesn't; the work happens where it sits. Buy a fob online and it will pair. Only if it's the right system; check first. A dead battery strands you. Hold the fob to the marked spot and the car starts.

Questions we get asked

Can you program a fob for a push-button start car?

Yes on most makes. It's done at the car, not a lot.

I lost my only fob. Does the car have to be towed?

No tow. A mobile locksmith works from the car.

Can the old fob be disabled?

Yes on most makes, at the same time the new one goes in.

What do you need from me?

Registration or title, photo ID, and the car's year and model.

Is a fob bought online worth trying?

Check with the technician before buying; many online fobs are the wrong system.