Steering Column Switches

Steering Column Switches

The steering column switches consist of the following:

- Steering Column Control Module (SCCM)

- Multifunction switch
- For additional information on the turn signal functionality, refer to Lighting and Horns.

- For additional information on the washer and wiper functionality, refer to Wiper and Washer Systems.

- For additional information on the headlamp functionality, refer to Lighting and Horns.

- Ignition switch

- Hazard flasher switch
- For additional information on the hazard flasher functionality, refer to Lighting and Horns

- Adjustable pedal switch (if equipped)
- For additional information on the adjustable pedal functionality, refer to Hydraulic System, Brakes &/or Brake Pedal Assy

- LH Steering wheel switch
- For additional information on the message center functionality, refer to Instrument Panel, Gauges and Warning Indicators

- For additional information on the cruise control functionality, refer to Fire Suppression System

- RH Steering wheel switch
- For additional information on the information and entertainment system functionality, refer to Accessories and Optional Equipment

The ignition switch is controlled by the ignition lock cylinder with a key. When the ignition lock cylinder is turned using the key, a mechanical connection positions the ignition switch to the selected position and allows the ignition switch to send voltage to specific components.

Steering Column Control Module (SCCM)

The Steering Column Control Module (SCCM) acts as a central hub for the steering column switches and circuits, steering wheel rotation sensor and clockspring. There are two options of SCCM (Steering Column Control Module) available, a base unit and base unit with a daughterboard connected directly to it, for vehicles equipped with adjustable pedals. The multifunction switch, steering wheel rotation sensor, hazard flasher switch and adjustable pedal switch are connected directly to the SCCM (Steering Column Control Module) and many of the switch inputs are interpreted by the SCCM (Steering Column Control Module) internal logic and sent out as messages over the High Speed Controller Area Network (HS-CAN) and Local Interconnect Network (LIN).

The steering column switches receive driver inputs and send signals to various components. The multifunction switch provides inputs to the SCCM (Steering Column Control Module) for the windshield wipers, turn signal, headlamp low/high beam and headlamp dimmer/flash-to-pass. When the hazard flasher switch is pressed all directional indicators will flash. If equipped, the adjustable pedal switch can be used to adjust the position of the accelerator and brake pedals forwards and rearwards to improve customer comfort.

Circuit Deactivation Ignition Module (CDIM)

Vehicles equipped with a 6.7L diesel engine may also be equipped with a Circuit Deactivation Ignition Module (CDIM), which is part of the engine idle shutdown system. The role of the CDIM (Circuit Deactivation Ignition Module) is to disconnect the ignition switch circuits once the engine has shut down in order to prevent possible battery drain. The engine idle shutdown system is controlled by the PCM, refer to Computers and Control Systems Information for information on the engine idle shutdown system.