How far away from your vehicle will your electronic key or smart fob work?
You key fob transmitter (your key) and receiver (your car) operate at a frequency of 315MHz (433.92MHz in Europe). You see, your key is actually a short-range radio transmitter.
Generally, the range is between 5 and 20 meters but there are some ways to extend that range.
Maximize Smart Fob Range – Car Key Distance
The classic trick of holding the key fob to your head will increase the signal distance by several car lengths which can also be helpful if your battery is low and the signal is weaker than normal.