Key fob replacement
Key fob replacement and remote programming
A fob that was lost, dropped once too often or went through the wash. Before replacing anything, it is worth finding out whether the problem is the fob, the battery or the car.
- 24/7Every day, including holidays
- 7+ yearsOperating locally
- Own techniciansLocksmiths who work for Mr Locksmith
- InsuredActive liability insurance
- English & EspañolAsk for either on the phone
Fob, battery or something else?
A key fob usually does two separate jobs: the remote buttons lock and unlock the doors by radio, and a transponder chip inside tells the immobilizer the key is genuine. One can fail while the other keeps working. A fob whose buttons stopped responding but still starts the car usually needs a battery or a repair, not a replacement.
Cold makes this worse. Coin-cell batteries lose voltage in an Illinois January, so a weak battery that worked in October can fail on the first sub-zero morning. If a new battery does not help, the problem may be a cracked circuit board, worn button contacts or a broken shell — all of which can sometimes be repaired by re-shelling the existing electronics.
When the fob does need replacing
A replacement fob has to match the vehicle's frequency, chip and button layout, and it has to be programmed twice over: the remote functions to the body control module and the transponder to the immobilizer. Many cheap fobs sold online are the wrong frequency, have the wrong chip, or are used units already locked to another vehicle and cannot be reprogrammed. If you have already bought one, call with the part number before booking so you know whether it will work.
Remote-head keys and flip keys
Remote-head keys (blade and buttons in one piece) and flip keys (a blade that folds into the fob) are both cut and programmed. Flip keys commonly fail at the hinge or the spring; a new shell with the original chip and board moved across is often a fraction of the cost of a new programmed key.
Car keys by make
Key types, immobilizer systems and all-keys-lost notes for each make. Call with the year and model to confirm what can be done for your vehicle.
Service Areas
Mobile service from Buffalo Grove
Mr Locksmith is based in Buffalo Grove and works within roughly 20 miles across Cook and Lake counties. There is no storefront — the technician comes to you.
How a call works
- Calls are answered 24/7
- Ask about the price on the phone
- Car, home and business work from the same mobile unit
- Insured — active liability coverage
Common questions
My key fob stopped working — do I need a new one?
Not necessarily. Try a fresh battery of the correct type first. If the car still starts with the fob, the transponder is fine and the remote side may only need a battery or repair.
Can you program a fob I bought online?
Sometimes. It must match the vehicle's frequency and chip, and it must not be a used unit locked to another car. Call with the part number before booking.
Why does my fob fail in winter?
Coin-cell batteries lose voltage in extreme cold. A battery near the end of its life often fails on the first very cold morning.
Locked out or need a lock fixed? Call (312) 478-6125.
We answer 24 hours a day, every day. Tell us where you are and what happened, and ask about the price before a technician is sent.