Don’t panic if your car key fob dies and you don’t have a spare battery. Most cars have backup ways to unlock and start the vehicle.
First, remove the hidden mechanical key inside the fob. Usually there’s a small sliding button on the back that releases it. Use this key to unlock the door. If you don’t see a keyhole, it may be hidden behind the door-handle cover.
To start the car, try pressing the dead key fob directly against the START button and push it. Many vehicles are designed to detect the chip this way even when the battery is dead. Some cars also have a hidden key-fob slot (often in the cup holder or center console) where you place the fob before pressing start. A few models still allow you to start the car by inserting the mechanical key into the steering column.
Other options include unlocking the car through the manufacturer’s mobile app, moving the fob closer to the door handle if the battery is just weak, or calling roadside assistance.
To avoid problems, replace the fob battery every couple of years (usually CR2032 or CR2025), keep it dry, and avoid leaving it in the car overnight since constant communication with the vehicle can drain the battery faster.