What to Do If Your Car Key Stops Working
Last updated: 3 August 2025
Step 1: Check the Key Fob Battery
A flat or weak battery is the most common reason for a car key fob to stop working. If the buttons don't respond or the range is very short, replace the battery with a fresh one (usually a CR2032 or similar).
Step 2: Try the Spare Key
If you have a spare key, try using it. This helps determine whether the issue is with the key or the car itself. If the spare works fine, your main key may need reprogramming or replacement.
Step 3: Manually Unlock and Start the Car
Some keyless cars still have a hidden key blade inside the fob. You can often manually unlock the door using this blade. Some vehicles also have a designated spot (e.g. under the steering column) to place a dead key fob to start the engine.
Step 4: Check for Interference or Deadlock Mode
Electronic interference from nearby devices or even low battery voltage in the car can affect key fob operation. Also, ensure your car isn't in 'deadlock' or anti-hijack mode, which may prevent unlocking with the fob.
Step 5: Inspect the Physical Key (If Applicable)
For older or physical keys, check for wear, damage, or debris in the keyway. Try turning the steering wheel gently while turning the key — a locked steering column can sometimes prevent it from turning.
Step 6: Contact a Locksmith or Dealer
If the key or fob is completely unresponsive and you're locked out or unable to start the car, contact an auto locksmith or your car dealership. They can provide a replacement key or reprogram your existing one.