Steering Wheel Switch Illumination Operation

The SIMA is internal to the LH upper steering wheel switch and controls the steering wheel and paddle switch illumination. The SIMA provides a pulse-width modulated voltage to the other switches on two circuits. All steering wheel and paddle switches are dimmable when the parking lamps are on.

The upper steering wheel switches are illuminated when the ignition is on. The RH upper steering wheel switch icons change depending on the mode the switch is in. The lower steering wheel switches are only illuminated when the cruise control system is on. The paddle switches are illuminated when the parking lamps are on.