Normal Operation
WARNING: This page is about a different car, the 2005 Mercury Montego, 2005 Ford Freestyle, and 2005 Ford Five Hundred. However, it is still accessible from the selected car via links, so may be relevant.
The smart junction box (SJB) sends a pulse-width modulated (PWM) voltage to the steering wheel controls through circuit 1417 (LG/RD) to the clockspring. The voltage passes through the clockspring to the steering wheel control harness and on to the steering wheel controls. Ground is supplied through the clockspring.