Normal Operation
WARNING: This page is about a different car, the 2006 Mercury Grand Marquis and 2006 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.
The lighting control module (LCM) supplies a variable pulse width modulated (PWM) voltage to the steering wheel control switches through circuit 484 (OG/BK). The steering wheel control switches are grounded through circuit 57 (BK).