4Keys Locksmith
NASTF VSP · Mobile Only · 24/7

I bought a key fob online. Can you program it?

Yes. If you sourced the fob or the key yourself, we program it to your vehicle. What decides whether it works is not where you bought it, it is whether it matches your exact car and has never been paired to another one. Read the FCC ID off the back when you call and you will know before anyone is dispatched.

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4Keys Locksmith Mobile Service

FL Licensed · GA Registered

Two registered entities

15,000+ jobs completed

Same Day Solutions

Rapid Mobile Dispatch

Arrival in 30 min

NASTF VSP

Vehicle Security Professional

9-sec avg phone answer

ALOA Certified

Pro Certified Technicians

25 technicians on rotation

The short answer is yes, and the useful answer is on the phone in a minute

Plenty of shops will not touch a fob they did not sell you. We will. The thing worth knowing is that the question has a right order: call with the FCC ID and your year, make and model before you buy, not after. That one call is the difference between a fob that programs in minutes and a fob that goes back in the post.

Smart key and fob serviceMy fob stopped working
What actually decides it

Four things decide whether your fob will take the programming

None of them are about the price you paid. All four can be checked on the phone before a van leaves.

The FCC ID on the back

Every fob carries an FCC ID and usually a part number moulded into the case. That is the single most useful thing you can read to us on the phone, because it tells us whether the fob you bought speaks the protocol your vehicle listens for.

The exact year, make and model

The same model can change key systems part way through a production run. A listing that says it fits a range of years is describing the shell, not always the electronics underneath it.

Whether the fob is unused

A fob that has never been paired to a vehicle can be written to. One that was already paired to a different car is a different situation, covered further down this page.

Whether the blade is cut

Most fobs still carry a mechanical blade for the door and the glovebox. If yours arrived uncut, it still has to be cut to your vehicle, and we do that on site.
Before you call

Four things to have in front of you

Two minutes of preparation is what keeps this from becoming a second appointment.

  1. 1

    Read us the FCC ID off the back of the fob

    It is printed or moulded on the reverse of the case, usually with a part number beside it. That one string tells us more than the listing title did, and it is the fastest way to know whether the fob will take the programming before anyone drives anywhere.

  2. 2

    Tell us the year, make and model of the vehicle

    Not the range from the listing. The specific vehicle, including the trim if you know it, because a mid-run change in key system is exactly what the listing will not have told you.

  3. 3

    Say whether the fob is new or came from another car

    A brand new unused fob and a used one pulled from a donor vehicle are two different conversations. Saying which one you have on the phone avoids a wasted visit.

  4. 4

    We come to the vehicle and program it there

    The vehicle has to be physically present for the programming, and 4Keys is mobile only, so the equipment travels to your car rather than the other way round. The blade is cut on site if it arrived uncut, and every function is tested before we leave.

When it does not work

Three ways an online fob goes wrong

We would rather tell you this before you buy than after. All three are avoidable with one phone call.

The listing said it fits and it does not

This is the common one. Marketplace listings are written to match as many searches as possible, so a fob sold as fitting your model may carry the wrong chip or the wrong frequency. Reading us the FCC ID before you buy prevents it entirely.

The fob is a clone of a real one

Some cheap fobs copy the case and the buttons without the licensed electronics inside. They look correct and they will not register. Nothing we do on site can fix that, and the money is spent before we arrive.

The fob was already married to another car

A used fob pulled from another vehicle holds that vehicle identity. We do not revive those, and the reason is below: a key that fails twice costs you far more than a key did.

Why we will not revive a fob that belonged to another car

A used fob pulled from a donor vehicle still holds that vehicle identity. There are ways to force one onto a second car, and we do not do it. When a key has already carried another identity, or has stopped being recognised by the car it belongs to, we do the job with a new key.

The reason is warranty rather than difficulty. A revived key is not something we are prepared to stand behind, and standing behind the work is most of what you are paying for. A key that fails in a parking garage at eleven at night does not cost you the price of a key, it costs you the evening.

If your own fob has recently gone dead, it is worth ruling out the cheap causes before assuming the worst. There is a step by step walkthrough on my key fob stopped working, and if there is no working key left at all, that is an all keys lost job with a different process.

You supplied the hardware. The authorization still applies.

Writing a key into a modern vehicle means writing to the module that stores key identity, and the security data for your VIN is released only through the manufacturer own channel, against proof the car is yours. Buying the fob yourself does not skip that step, and you would not want it to: it is the same rule that stops anyone else buying a fob for your car and having it programmed.

What NASTF VSP authorizesVerify any locksmith in 60 seconds

FAQ - Programming a Fob You Already Own

Got questions? We have answers. If you don't see your question below, call us anytime - we're available 24/7.

Yes. If you sourced the fob yourself, we program it to your vehicle. What decides whether it works is not who sold it to you, it is whether the fob matches your exact vehicle and has never been paired to another one. Read us the FCC ID off the back when you call and you will get a straight answer before anyone is dispatched.
It is a short alphanumeric string printed or moulded on the back of the fob case, normally alongside a part number. It identifies the radio module inside. It is the single most useful thing you can tell us on the phone, because a listing title can be wrong about fit and the FCC ID cannot.
Yes, and that is the better order to do this in. Call with the year, make and model of the vehicle and the FCC ID from the listing, and you will get an answer before your money leaves. It costs nothing and it is the difference between a fob that programs in minutes and a fob that goes back in the post.
No. Most aftermarket fobs ship with an uncut blade, which is normal. We cut it to your vehicle on site, so it opens the door and the glovebox as well as starting the car. Tell the dispatcher it arrived uncut so the right blank and the cutting equipment are on the van.
We do that work with a new key rather than a used one. A fob that has already carried another vehicle identity is not something we are willing to warranty, and on a car you depend on, a key that stops being recognised a second time costs you the day, not just the callout. It is a deliberate policy rather than a technical limit.
Same answer, and for the same reason. When a key has quit we replace it rather than try to revive it. If your fob has gone dead recently it is worth ruling out the coin cell first, which costs almost nothing, and there is a diagnostic walkthrough for that on our key fob page.
No. 4Keys is mobile only, so there is no shop and no counter to visit. The vehicle has to be present for the programming to happen, so the equipment comes to wherever the car is: your driveway, your office car park, or the side of the road.
Yes, and that does not change because you supplied the hardware. The programming still runs through the manufacturer own channel, which releases the data for a specific VIN only against proof of ownership. It is the same rule that stops somebody else buying a fob online and having it programmed to your car.
We run manufacturer software for American, German, Japanese and Korean makes, authorized through NASTF Vehicle Security Professional. If you are unsure whether your vehicle is covered, the year, make and model on the phone will settle it in under a minute.
That depends on the vehicle, and it is worth asking before we start. Some systems add a key to the existing list, others require every key to be present and rewrite the whole list, which means any key not in your hand that day stops working. Tell us how many keys you have and we will tell you which case yours is.
Yes, though it is a different job from adding a fob to a car that already starts. With no key in existence the security data for your VIN has to be requested through the manufacturer channel and the blade cut to code rather than copied. That is an all keys lost job, and it has its own page.
Yes, dispatch runs 24 hours in both Miami-Dade and Metro Atlanta. After hours work carries a separate surcharge, which is stated on the same call rather than discovered on the invoice.

The rest of what the van does at your car

Each service has its own page with the process and what arrives with the technician.

Car Lockout

Mobile car lockout 15-30 min, no damage

See service

Lost Car Key Replacement

Mobile cut and OEM programming on-site

See service

Car Key Programming

Transponder, smart key, proximity fob pairing

See service

Ignition Repair

Cylinder replacement, Mercedes ESL, BMW EWS

See service

Broken Key Extraction

Snapped key removal without drilling

See service

Car Key Duplication

Spare keys, copies, transponder cloning

See service

Trunk Lockout

Mobile trunk opening 15-30 min

See service

ECU & Module Programming

ECU, BCM, PCM, TCM flashing and coding

See service

Luxury Key Programming

Mercedes, BMW, Range Rover, Audi, Porsche, Bentley

See service

Related Reading

Diagnosing a dead fob, checking a credential, and what the dealer route actually involves.

My key fob stopped working

Six checks that separate a dead coin cell from a failed receiver, before you pay anyone.

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Do locksmiths have dealer software?

What NASTF VSP authorizes, what a company must prove to hold one, and how to check.

Read guide

Locksmith vs dealer car keys

Cost, time and warranty compared for the same job done two different ways.

Read guide
24/7 Live Dispatch

Read us the FCC ID

That string off the back of the fob, plus the year, make and model of your car. That is enough to tell you whether it will program, before anyone is dispatched.

See PricingSmart key and fob serviceNASTF VSP explained