What happens if the spare car key is not used for a long time?

[DelKathryn]

If the spare car key is not used for a long time, it will automatically drain the battery, so the battery should be removed when not in use. The method to replace the car key battery is as follows: 1. Remove the mechanical key; 2. Insert a flat-head screwdriver into the bottom "open" position and pry it up and down; 3. Once a gap appears, use the screwdriver to pry open the key along the gap; 4. Remove the old battery and replace it with a new one; 5. Reassemble the key. The working principle of a car key is: it emits a weak radio wave from the owner, which is received by the car's antenna. After the electronic controller identifies the signal code, the system's actuator performs the action of locking or unlocking. The functions of a car key include: 1. Remote locking and unlocking of the door; 2. Press and hold the lock button after turning off the engine to close the windows; 3. Press the horn-shaped button to locate the car.