You Can Still Start Your Car With A Dead Smart Key: Here's How

While cars with features like large screens to use Apple CarPlay effectively and dashboards fitted with cool accessories have certainly made our lives easier, technology can prove to be a bane in certain situations. For instance, a mechanical key could be used to unlock and start a car without any batteries. But if your smart key dies on you, you may be stuck — until you figure out how to make it work even without a cell.

Smart keys rely on radio communication exchanged between your key fob and your car's computer system. Similar to Bluetooth, this means you'll need to be within a detectable range for your car to register your smart key commands. Some vehicles can even be unlocked just by touching the door handle with the key in proximity. While these features are convenient, what exactly does one do when the battery in a smart key fob decides to take an unexpected vacation? Thankfully, there are a few failsafes you can rely on should this situation occur.

First and foremost, it's always a good idea to travel with emergency supplies in your vehicle, like a car charger if your phone runs out of juice, a tire inflator in case you end up with a flat tire, or even a spare key for situations where your primary fob just won't work. We also recommend having a spare set of batteries for your keys. Many key fobs use coin cell batteries, with the CR2032 and CR2025 types as the usual suspects. Of course, replacing the fob battery is only achievable if you're able to get inside your car.

For those stranded outside the vehicle, one of the first things you can check is whether your smart fob features a hidden physical key. Manufacturers often include some type of slotted mechanism that conceals a secondary physical key that can lock and unlock at least one door. Some hideaway keys can operate your vehicle's ignition system, too, if you're lucky. It's also a good idea to lend your spare key fob to a trusted individual who can swing by quickly, or store it in a safe and secure location that you can access at any time.

Depending on the make and model of your vehicle, you may still be able to start it with a dead key fob. Hyundai, for instance, provides detailed instructions on how to start a vehicle with a dead fob by simply holding down the brake pedal while pressing the fob into the car's start button — instead of using your hand to do so. Several vehicle manufacturers use this backup method for starting a car with a dead fob, while others rely on hidden key fob slots inside the vehicle.

Ford is one company that offers backup slots, and these hidden compartments can usually be found built into your vehicle's cup holder, center console, or steering column. Simply place the fob in the relevant compartment and press the ignition start button. If your vehicle came with a smart key fob, it may also be supported by a companion app with remote lock and unlock capabilities. Some electric vehicles can even be started remotely via a smartphone, making it easy to drive to a local store to find replacement batteries.