Here's What Happens If You Drive Off Without Your Car's Key Fob

Traditionally, drivers had only a metal key to start their vehicle, which made it impossible to venture off without it. However, it was the 2003 Mercedes-Benz that became the first to offer starting functionality from a smart key. Today, key fobs have become more commonplace across the industry. In fact, many new cars don't come with keys anymore; instead, they rely on key fobs that utilize proximity technology and low-frequency radio waves to communicate with the starter button. While your car may have a key fob holder, what if instead of being safely secured inside your vehicle, you somehow drove off and left it behind? 

Fortunately, there's no need to speculate, as this scenario has been tested by curious motorists. The answer? Nothing happens, at least initially. The vehicle will continue to operate normally, albeit with perhaps some audible warnings alerting you that the car can't sense the fob. However, once you stop and shut off your engine, you're stuck, as the ignition won't operate without registering the key fob. If, for some reason, the engine cuts out at any point during your journey without the key fob, you will be stranded, which is why even short trips are risky without it.

As these remote keyless features have become more advanced, the price of replacing the key fob itself has also climbed. If you manage to lose your fob, a new one from the dealership will run anywhere from around $50 to more than $100. Before you can use it, the key fob must be programmed, which may or may not incur a labor charge from the dealer.

Fortunately, automakers have addressed this issue with some backup options that can help you out in a pinch. For example, there are hidden features you might not know about on your car's key fob, which may include a mechanical key. This physical key can help you gain access to the interior of the car, but what about starting it?

While a few models may offer a hidden keyhole somewhere on the dash for starting it with a physical key, not every vehicle includes it. But, even if you only have a start button and your fob battery has died, there is still another option. Several manufacturers have included a special backup feature, where you can simply press the key fob into the start button, and the contact between the two is enough to get the engine fired up. Essentially, this works by leveraging electricity from your vehicle's battery that can magnetically transfer temporary energy into the fob so it can transmit.

Lastly, if you're enrolled in something like the Hyundai Digital Key service, you can utilize a smartphone app to start your car if needed. These applications can essentially do everything a key fob can, with the Hyundai service going a step further and allowing you to loan out a digital key to a friend or family member.