Walk away lock systems automatically lock the vehicle when the driver moves away with the key, eliminating the need to press any button. While incredibly convenient, these systems have security implications that every owner should understand and address. ## How Walk Away Lock Works Walk away lock uses a proximity sensor in the vehicle that detects the distance between the car and the key fob. When the key is detected moving away from the car, the system automatically locks all doors and arms the alarm. The detection range is typically 2-5 metres, depending on the vehicle and key signal strength. The system detects when the key moves beyond this range and locks the car automatically. Some systems require the driver to actively walk away, locking after two or more steps. Others lock when the key is within a specific range of the car and that distance increases. The exact behaviour depends on the manufacturer and can often be adjusted in the settings. Approach unlocking works in the opposite direction. When the key approaches the car within range, the vehicle unlocks automatically, ready for entry. This makes the entire locking and unlocking process completely hands-free. ## Keyless Entry and Relay Attacks The convenience of keyless entry comes with a significant security vulnerability known as relay attack. Criminals use simple radio equipment to extend the range of the key's signal, tricking the car into thinking the key is present when it is actually elsewhere. A relay attack involves one criminal standing near the car with a receiver while a second criminal walks toward the key with a transmitter. The receiver picks up the car's challenge signal and relays it to the transmitter near the key. The key responds, and this response is relayed back to the car. The car unlocks and can be driven away. These attacks can take less than a minute and require no forced entry or damage. The car is effectively stolen using the owner's key without their knowledge. ## Protecting Against Relay Attacks The most effective protection is to store the key in a Faraday pouch or metal tin that blocks radio signals. These pouches are inexpensive and effectively prevent relay attacks by blocking all key signals when the key is not in use. Some newer vehicles have motion-detecting keys that go to sleep if the key has not moved for a period of time. This prevents relay attacks because the key must detect motion before responding to the car's challenge signal. Checking that your car has locked after walking away is a good habit. If the indicators do not flash and the mirrors do not fold, the car may not have locked. Some vehicles have audio confirmation of locking. Disabling keyless entry entirely, where the option is available, eliminates the relay attack vulnerability but removes the convenience of passive entry. This trade-off is personal preference. ## Frequently Asked Questions **Can I turn off walk away locking?** Most vehicles allow walk away locking to be disabled through the infotainment system settings. Consult your owner's manual for the specific procedure for your vehicle. **Do relay attacks work on all keyless cars?** Relay attacks work on most keyless entry systems. However, vehicles with ultra-wideband keyless entry technology are resistant to relay attacks because they measure the distance to the key, not just whether a signal is present. **Does locking my key in a Faraday pouch flatten the battery?** No. The key uses no power when signals are blocked by the Faraday pouch. The key battery typically lasts two to three years regardless of how it is stored.