How to Unlock and Start Your Car When the Key Fob Battery is Dead

The coin batteries in automotive key fobs only last for a few years. But if they happen to die and you’re caught unawares, auto manufacturers have designed these little-known backup methods to enter and start your vehicle.To the right of your driver’s door handle, you’ll see this cap. On the underside is a notch. You can stick the blade of the key into this notch to pry the cap off. This reveals a conventional lock cylinder. If your fob does not have the switchblade key, it likely has a hidden conventional key sheathed within the fob. Look for parting lines to work out where it is. As for starting the car: Some manufacturers, like Volkswagen, have a dedicated area on the side of the steering column with an icon of a key on it. If you hold your fob against this area, an induction loop in the steering column powers the immobilizer chip inside the fob, even if the battery is dead; and when you press the ‘Start’ button, the engine should turn on. Other manufacturers, like Honda, have the induction loop hidden behind the start button itself. So you press the button with your dead fob, and presto. If your car is made by Audi, BMW, Cadillac, Chevrolet, Ford, GMC, Honda, Hyundai, Jaguar, Kia, Land Rover, Lexus, Mercedes‑Benz, Nissan, Porsche, Subaru, Toyota, Volkswagen or Volvo, it’s likely equipped with these features.