Keyless Entry Keypad
WARNING: This page is about a different car, the 2015 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
The keyless entry keypad is a touch-sensitive capacitive sensor integrated into the front door window moulding. When a finger touches the keypad, it changes the capacitance of the sensor in the area of the finger touch. The keypad determines which area is touched and provides a ground signal to the corresponding voltage reference circuit(s). The keypad only works when touched with a finger. The keyless entry keypad may not work when gloves are worn. The gloves act as an insulator and do not allow the finger to change the sensor capacitance.