Last Updated on January 22, 2025 by Elizabeth
Have you ever returned to a parking lot or garage and realized you’d forgotton where you parked? Or maybe after you’ve walked away from your parked vehicle, you had a moment of doubt as to whether you locked the car. If you’re standing out of range, your car key fob won’t work. But we’ve got some easy ways to fix that. Here’s how to extend the range of your key fob.
How a Car Key Fob Works
A car key fob contains a short-range radio transmitter (typically a RFID chip) and an antenna. It uses radio signals to communicate with an RFID reader in the car’s receiver unit, usually located near the car’s locking system. When you press button on the fob, it sends a signal to the receiver, which interprets the code and performs the requested action, like locking or unlocking the car.
Ask AutoSlash for a Quote on a Cheap Car Rental
The range of key fobs varies, depending on the make and model of the car. Typically you’re talking about around 75 to 100 feet, but there are some easy ways to extend the range of a key fob.
Car Key Fob Not Working? Try These Tips.
Hold the fob higher
Key fobs work over ultrahigh-frequency radio waves, which theoretically don’t require a direct line between transmitter and receiver to work. Still, the radio waves can travel farther when there is no obstruction, since radio waves reflect, diffract, and refract when they encounter various materials. Obstacles like cement barriers, large trees, or even other electronic devices can interfere with the signal, reducing the effective range. Holding the key fob up high when you press the button to lock or unlock can give the signal a better chance of reaching its target. The basic rule of thumb: The less stuff in between the fob and the car, the farther the signal will travel.
Use your head
This is a fun one. Holding a key fob to your head (try your chin or jaw) can extend the signal range. This works because the fluids inside your skull can act as a conductor. Basically, you are turning your head into an antenna that amplifies the radio waves. An open secret among auto mechanics, this trick has been shared by numerous YouTubers and TikTokkers, some of whom found it can extend a fob’s range by another 15 feet. Here’s a Top Gear video from 2008 demonstrating the trick.
Other body organs also work. The brain and heart are made up of about 75% water, and the lungs are about 83% water. Holding the fob to your chest can also extend its range.
Use a bottle of water
If you happen to be holding a full water bottle or cup of coffee or any water-based liquids, the same principle comes into play. Water molecules effectively transmit radio waves, which are the signals used by key fobs, thus boosting the signal strength when the fob is near a water source. When trying to unlock your car from a distance, simply hold the key fob firmly against the water bottle while you press the button.
Use a bottle of Gatorade
One YouTuber found that pressing a key fob to a bottle Gatorade extended the fob’s range farther than when he used his head or a water bottle. He chalked up the better conductivity to Gatorade’s electrolytes.
Let AutoSlash Track Your Car Rental for Price Drops
Use gravity
A fob’s range will be much better if you are at a significant height above the car. The aforementioned YouTuber proved this while standing on a fourth-story balcony overlooking a parking lot where his car was parked well outside of the fob’s normal range. This hack could come in handy at, say, an airport where you might have an parking garage next to an enormous long-term parking lot.
Change the battery in the fob
This may seem obvious, but key fobs work optimally with a healthy battery. If your fob fails to work from a reasonable distance or only works intermittently, the most straightforward remedy is to replace its battery. Fobs usually take coin or button cell batteries, which you can find at most hardware and grocery stores. The car owner’s manual (hopefully located in the glove box) or an online video can tell you how to open the fob, remove and replace the old battery, and then put everything together again.
Related:
