Steering Wheel Switches

WARNING: This page is about a different car, the 2014 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

The RH upper and lower steering wheel switches contain series of resistors. Each steering wheel switch function corresponds with a specific resistance value within the switch.

The APIM sends a 5-volt reference voltage to the RH upper steering wheel switches on the input circuits. When a switch is pressed, the voltage is routed through the corresponding resistor(s), and then to ground through the APIM . The APIM monitors the resultant voltage drop to determine which switch was pressed. The voltage drop varies depending upon the resistance of the specific switch pressed.

The IPC sends a 5-volt reference voltage to the RH lower steering wheel switches on the input circuits. When a switch is pressed, the voltage is routed through the corresponding resistor(s), and then to ground through the IPC . The IPC monitors the resultant voltage drop to determine which switch was pressed. The voltage drop varies depending upon the resistance of the specific switch pressed.