Symptoms
- Push-button start works normally
- Lock/unlock buttons on the fob do nothing
- Doors can still be locked/unlocked manually or with interior buttons
- Started suddenly with no other symptoms
Likely causes
- CommonWorn or stuck lock/unlock button on the fobButtons pressed thousands of times can wear out independently of the fob's other functions.
- PossibleWeak battery affecting only lower-priority functionsSome systems prioritize power for starting over remote lock/unlock, so a weak battery shows here first.
- PossibleDoor lock actuator or module issueIf the fob's signal is fine, the fault may be in the car's door lock mechanism rather than the fob.
- Less commonFob programming partially lostA fob can lose specific function programming while others remain intact, especially after a battery disconnect.
What to do
- Replace the fob battery, since a weak one can selectively affect lock/unlock before starting stops working.
- Press the lock and unlock buttons firmly and listen for a click, checking if the buttons feel physically stuck or spongy.
- Test the interior lock/unlock buttons and the key blade manually to confirm the doors themselves work.
- Try a second fob if available to see if the problem follows the fob or stays with the car.
- If a second fob also can't lock/unlock but starts the car fine, suspect the car's door lock module rather than the fobs.
- If only one fob is affected, it likely needs reprogramming or replacement.
Tools and parts
- Small screwdriver
- Replacement coin-cell battery
Key fob batterySearch: “key fob battery for your car model”
When to call a pro
If a second fob shows the same issue, have a dealer check the door lock module; if it's fob-specific, it likely needs reprogramming.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.