Prior to February 2001, most SmartWheels connected to the Master Control via a dual slip-ring assembly in the steering column. Steering Wheel item numbers PC209x utilize two wires for this purpose. The yellow wire is the multiplex Signal wire and the brown wire is the multiplex Ground wire. The controls on these wheels are not backlit.
Since February 2001 steering columns equipped with clock-springs have been widely used in motor homes. The clock-spring is a device in the steering column that allows continuous electrical connections through the rotation of the column without sliding contacts. The availability of the clock-spring has allowed the transmission of sufficient power through the column to backlight the steering wheel controls. Steering Wheel item numbers PC210x and PC217x utilize four wires for this purpose. These controls on these wheels are backlit."
BACKLIT STEERING WHEEL
On Steering Wheels mounted on clockspring- equipped steering columns the Steering Wheel switch pads are backlit by LEDs. It may be necessary to look directly at the switch pads through cupped hands to see the backlighting in
daylight. If the backlighting is not working, remove the center pad from the Steering Wheel as
described above. Measure the DC voltage between the black and green wires on the Steering Wheel.
There should be 12 Volts present when the IGNITION is on. If not check the 3 Amp fuse on the Master. If the fuse is good, check for 12 Volts on J1.4 on the Master. If there is 12 Volts present at J1.4 on the Master and not at the steering wheel then check the wiring between the master and the Steering Wheel. If there is 12 Volts present at the Steering Wheel and the backlighting is not working, replace the Steering Wheel. www.vipwheels.com/WEB%20PAGES/techsupport.html