Symptoms
- Pressing buttons does nothing
- No click or light on the fob
- Doors don't lock or unlock remotely
- Car may still start with the fob inside if it has push-button start
Likely causes
- CommonDead or weak coin-cell batteryFobs use small batteries that typically last 1–3 years and fail gradually then suddenly.
- PossibleFob dropped in water or damagedCorrosion on the internal contacts can stop the buttons from working even with a fresh battery.
- PossibleLost programming/pairing to the carA fob can become unpaired after other key work or a dead 12V battery reset.
- Less commonBroken button or cracked circuit boardYears of use can crack solder joints, especially on fobs that get dropped often.
What to do
- Try the fob very close to the door handle or start button; weak batteries sometimes still work at short range.
- Open the fob case (usually a small slot for a coin or screwdriver) and note the battery type printed inside, often CR2032 or CR2025.
- Swap in a fresh battery of the same type, oriented the same way as the old one, and snap the case shut firmly.
- Test the buttons again; if it works, you're done.
- If still dead, check for visible corrosion or water damage inside the fob and let it dry fully if it got wet.
- If the car has a physical key blade inside the fob, use it to unlock the door and check the owner's manual for the backup start procedure.
- If a fresh battery doesn't help, the fob may need to be reprogrammed or replaced by a dealer or locksmith.
Tools and parts
- Small screwdriver
- Replacement coin-cell battery
Key fob batterySearch: “CR2032 or CR2025 key fob battery (check fob for exact size)”
When to call a pro
If a new battery doesn't fix it, or the fob needs reprogramming, an auto locksmith or dealer can reprogram or replace it, usually while you wait.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.