Replacement Car Key Fob London — Supply, Programme & Pair at Your Location
Has your car key fob stopped locking or unlocking the vehicle? Is it physically broken, lost, or simply worn out? Keylux provides a professional replacement key fob service across London — we supply the correct fob for your vehicle, programme it to your car's ECU, and test it fully, all at your location.
We cover all major makes and models including Ford, BMW, Mercedes, Audi, Vauxhall, VW, Toyota, Peugeot, Renault, Nissan and more. Fast mobile response, transparent pricing, available 24/7.
All Makes
Ford, BMW, Audi, Mercedes, VW, Toyota, Vauxhall, Peugeot & more.
Supply & Programme
We bring the right fob and programme it to your vehicle — one visit, fully working.
24/7 Mobile
Available nights, weekends and bank holidays. We come to you anywhere in London.
What Is a Car Key Fob — and Why Does Replacement Require Programming?
Key fobs are more than just a plastic casing — they contain security technology that must be paired to your specific vehicle.
A car key fob is the remote unit that allows you to lock and unlock your vehicle, and on many modern cars, to start the engine without inserting a key. Inside every fob is a radio frequency transmitter and — in most cases — a transponder chip that communicates with your vehicle's immobiliser system.
When you press a button on your fob, it sends an encrypted rolling code to your car's receiver. The vehicle checks the code, and if it matches the expected value, it responds — locking, unlocking, or disarming the alarm. Because this code is unique to your vehicle, a generic fob or a fob from another car of the same make will not work — it must be programmed to your specific vehicle's ECU.
This is why simply buying a replacement fob online and expecting it to work is a common and frustrating mistake. The fob must be supplied and programmed together — and Keylux does both in a single mobile visit, at your location.
⚠️ Online Replacement Fobs Will Not Work Without Programming
A key fob purchased from eBay, Amazon, or any online retailer needs to be programmed to your specific vehicle before it will function. This requires specialist OBD diagnostic equipment. If you have already purchased a fob online, call us — we can programme it to your vehicle on site in most cases, saving you the cost of a new one.
Types of Key Fob We Replace
Modern vehicles use several different fob formats. We supply and programme all of the following.
Remote Flip Key Fob
A folding key where the blade flips out of the fob housing. Common on Ford, Vauxhall, Peugeot, VW, and Seat. We replace both the fob and blade, programming the transponder chip and remote simultaneously.
Separate Remote Fob
A standalone remote fob used alongside a separate key blade. Found on older BMW, Mercedes, and Audi models. The fob controls locking and alarm; the blade starts the ignition independently.
Smart Key / Proximity Fob
A keyless fob that allows entry and push-button start when in your pocket. Found on newer Audi, BMW, Mercedes, Toyota, Ford, Kia, Hyundai and most modern vehicles. Requires specialist smart key programming.
Key Card
A flat card-style key used by Renault and some Dacia models. Works via contactless proximity — must be programmed to the specific vehicle. We supply and programme replacement Renault key cards on site.
Integrated Blade & Fob
A single unit containing both the key blade and remote fob circuitry in one fixed housing. Common on Toyota, Honda, and Nissan. The entire unit must be replaced and reprogrammed if either function fails.
Shell / Case Replacement
If your fob electronics still work but the casing is cracked or broken, we can transfer the internal components to a new shell in many cases — a more cost-effective option than full replacement. Call us to confirm if this applies to your fob.
Signs You Need a Replacement Key Fob
Key fob problems are not always obvious. Here are the most common signs that your fob needs replacing — or has already failed.
The fob no longer locks or unlocks the car, even at close range. Battery replacement has not fixed it.
A new battery should restore fob function. If it doesn't, the internal circuitry or transponder chip has failed.
Physical damage can expose the internal circuit board to moisture and dirt, causing intermittent or total failure.
On keyless entry vehicles, if the car won't recognise the fob for push-button start, the proximity transponder may have failed.
Inconsistent fob behaviour usually signals a dying circuit board or a chip that has partially lost its programming.
A lost or stolen fob should be replaced and the old fob's code deleted from the ECU immediately for security.
Key Fob Replacement — Vehicle Makes We Cover
We supply and programme replacement key fobs for all major vehicle makes across London.
| Vehicle Make | Fob Type | Remote Programming | Smart / Keyless |
|---|---|---|---|
| Ford (Fiesta, Focus, Kuga, Puma, Transit) | Flip key fob / Intelligent Access | ✓ Yes | ✓ Yes |
| BMW (1–8 Series, X-Series, Mini) | Comfort access / Remote fob / Display key | ✓ Yes | ✓ Yes |
| Mercedes-Benz (A–S Class, GLC, GLE) | Smart key / Comfort key / Infrared | ✓ Yes | ✓ Yes |
| Audi (A1–A8, Q2–Q8, TT, e-tron) | Flip fob / Advanced Key proximity fob | ✓ Yes | ✓ Yes |
| Volkswagen (Golf, Polo, Passat, Tiguan) | Flip key fob / Keyless remote | ✓ Yes | ✓ Yes |
| Vauxhall (Corsa, Astra, Insignia, Mokka) | Flip key fob / Remote fob | ✓ Yes | Selected models |
| Toyota / Lexus (Yaris, Corolla, RAV4, CH-R) | Smart key / Integrated blade fob | ✓ Yes | ✓ Yes |
| Peugeot / Citroën | Flip key fob / Remote fob | ✓ Yes | Selected models |
| Renault / Dacia | Key card / Remote fob | ✓ Yes | Selected models |
| Nissan (Juke, Qashqai, Micra, Leaf) | Intelligent Key / Remote fob | ✓ Yes | ✓ Yes |
| Kia / Hyundai | Smart key / Flip fob | ✓ Yes | ✓ Yes |
| Land Rover / Range Rover | Smart key / KESSY proximity fob | ✓ Yes | ✓ Yes |
Don't see your make listed? Call us — we cover most vehicles and will confirm immediately before you book.
Why Choose Keylux for Key Fob Replacement in London?
- We supply and programme — not just one or the other. Full service in a single mobile visit.
- All major makes and models covered — Ford, BMW, Audi, Mercedes, VW, Vauxhall, Toyota, Renault, Nissan, Kia and more.
- Already bought a fob online? We can programme it to your vehicle on site in most cases — saving the cost of a second unit.
- Fully mobile — we come to your home, workplace, car park, or roadside anywhere in London.
- Available 24/7 including nights, weekends and bank holidays.
- Stolen fob — old code deleted and new fob programmed in the same visit for full security.
- Transparent pricing — exact quote given before any work begins. No surprises.
How Our Key Fob Replacement Service Works
From first call to fully working fob — a simple, single-visit process.
Call & Describe
Tell us your vehicle make, model, year, and what the fob problem is — not working, broken, lost, or stolen. We confirm we can help and give you a quote over the phone immediately.
We Come to You
A mobile fob replacement specialist is dispatched to your exact location anywhere across London. We carry the correct fob units and programming equipment for most common vehicles.
Supply & Programme
We supply the correct replacement fob for your vehicle, cut the blade if required, and programme the fob to your car's ECU using specialist OBD diagnostic tools at the roadside.
Test & Confirm
We test all fob functions fully before we leave — remote locking, alarm, boot release, and keyless start if applicable. You leave with a fully working replacement fob.
Replacement Key Fob Prices in London
The cost of a replacement key fob in London depends on your vehicle make and model, the type of fob required (standard remote, flip key, or smart proximity key), and whether the blade also needs to be cut. Premium brands such as BMW, Mercedes, and Audi use more sophisticated fob technology, which is reflected in the cost of both the unit and the programming.
As a mobile auto locksmith, Keylux is typically considerably cheaper than a main dealer or manufacturer, without any reduction in the quality of the fob unit or the accuracy of the programming. And unlike a dealer, we come to you.
If you have already purchased a replacement fob online and simply need it programmed, call us — in many cases we can programme your existing unit on site for a fraction of the cost of a full replacement.
We always confirm the exact price before any work begins. For general key replacement pricing information, see our car key replacement cost guide. For a specific fob quote, call us now and we will advise immediately.
Areas We Cover for Key Fob Replacement in London
Our mobile key fob specialists cover South and Southwest London and the surrounding areas. Click any location to see our dedicated local service page.
Not sure if we cover your area? View our full coverage map or call us directly to confirm immediately.
Frequently Asked Questions — Replacement Key Fob London
Common questions from drivers who need a replacement key fob across London.
If a new battery does not restore fob function, the internal circuit board or transponder chip has likely failed. Alternatively, the fob may have lost its synchronisation with the vehicle — which can sometimes be restored by re-pairing, but in most cases requires a replacement fob that is freshly programmed. Call us and describe the issue — we will advise before dispatching.
In most cases, yes. If you have purchased a compatible replacement fob for your vehicle, we can programme it to your car's ECU on site using our OBD diagnostic equipment. This is often the most cost-effective route. Call us with your vehicle make, model, year, and the fob reference to confirm compatibility before we arrive.
In most cases, replacement fob programming is completed within 30 to 60 minutes on site. Smart key and proximity fob programming on premium brands such as BMW, Audi, or Mercedes may take up to 90 minutes. All work is carried out at your location — no need to visit a garage or wait for a dealer appointment.
If your fob has been lost or stolen, we strongly recommend having the old fob's code deleted from your vehicle's ECU as soon as possible. A stolen fob could be used to unlock or — on keyless vehicles — start your car. We can delete the stolen fob's code and programme a fresh replacement in a single visit. See also our car lockout service if you are currently unable to enter your vehicle.
Yes. We supply and programme replacement smart keys and keyless proximity fobs for all major makes including Ford Intelligent Access, BMW Comfort Access, Audi Advanced Key, Mercedes Keyless-Go, Toyota Smart Key, Kia Smart Key and more. See our dedicated smart car keys London page for more detail.
In almost all cases, yes — considerably cheaper. Main dealers charge a significant premium for key fob supply and programming. Keylux provides the same quality of fob and the same standard of programming at a more competitive rate, at your location, often the same day. For a full comparison, see our locksmith vs dealership guide.
Not necessarily. In many cases, the internal electronics from a damaged fob can be transferred into a new shell — saving the cost of a complete replacement and reprogramming. Call us and describe the damage. We will advise whether a shell swap is possible for your specific fob, or whether a full replacement is the more reliable option.
We carry a range of the most common replacement fobs in our mobile units for popular makes including Ford, Vauxhall, VW, Peugeot, and others. For premium brands or less common models, we may need to source the correct unit — but in most cases this is a same-day or next-day turnaround. Call us and we will confirm stock availability immediately.
Key Fob Not Working Right Now? Here's What to Do
If your key fob has stopped working and you cannot access or start your vehicle, follow these steps:
- Try the physical key blade — most fobs contain a hidden emergency blade that can unlock the door manually even when the fob has failed.
- Replace the fob battery first if you haven't already — a CR2032 or similar coin cell is the most common type and costs under £2.
- If neither resolves the issue, call Keylux — describe your vehicle make, model, and the exact symptoms and we will advise and dispatch immediately.
- If your fob was stolen, call us as soon as possible to have the stolen code deleted before the vehicle is at risk.
Related Services You May Need
Alongside key fob replacement, Keylux provides a full range of mobile auto locksmith services across London.
Transponder Key Programming
Specialist transponder chip programming for all makes — key turns but car won't start? We can help.
Smart Car Keys London
Keyless entry and push-button start key replacement and programming for all modern vehicles.
Car Key Replacement London
Full mobile car key replacement — cutting and programming in a single visit for all makes.
Car Lockout Service
Locked out of your car because your fob has failed? Fast, damage-free mobile entry across London.
Need a Replacement Key Fob in London?
Call Keylux now for fast, mobile key fob supply and programming anywhere across London. We quote before we start — no obligation, no hidden charges.