You've put a fresh battery in your car key fob, and the buttons still do nothing, or the car still says "key not detected". It's a common problem, and most of the time it's something small. Work through these.
1. The battery is the wrong type
Most fobs take a 3V coin cell, and the common sizes look alike. A CR2025 is thinner than a CR2032, so it can sit loose and lose contact; a CR2016 is thinner still. Use exactly the type printed on the old battery or in your manual.
2. It's upside down
The positive (+) side, with the writing, usually faces one way in the case. Take a photo before you remove the old battery, then match it.
3. The contacts were bent
Prying the case open can bend the small metal tabs that touch the battery. Gently ease them back so they press on the cell.
4. The new battery is old or poor quality
Coin cells lose charge sitting on a shelf, and cheap ones can arrive nearly flat. Try a fresh one from a good brand.
5. The case isn't closed properly
If the two halves aren't clicked shut, the battery or the button pad may not seat properly. Press around the edges until it closes evenly.
6. The fob needs to resync
Some older remotes need re-synchronising after a battery change: often a matter of pressing a button within range of the car, or locking and unlocking with the mechanical key. Your owner's manual will say if yours needs it.
7. The fob itself is damaged
A drop or water damage can break the fob's circuit. A good test: try your car's backup start method (on many cars, holding the fob against the start button or a marked spot). If the car starts, the transponder chip is fine and only the remote side has a problem.
Getting in and started meanwhile
- Door: most smart keys hide a mechanical key; the driver's door has a keyhole, sometimes under a cap on the handle.
- Start: most keyless cars have a backup method for a weak fob. Brand-by-brand steps: Toyota · Honda · BYD · BMW · Mercedes-Benz · all brands.
When to call
If your only working key has stopped working, get a spare made while you still have one that works: we clone key fobs for all major brands from a working key, after checking your NRIC against the car's log card. If you're locked out, we open cars without damage, 24/7 islandwide. Call or WhatsApp 9224 9224.
Down to one key? WhatsApp 9224 9224 your car's model, year and a photo of the key for a spare.