Steering Column Switches

Steering Column Switches

Principles of Operation

Ignition Switch

When the ignition lock cylinder is turned using the key, a mechanical connection positions the ignition switch to the desired position. The available ignition switch positions are:

- OFF

- ACC

- RUN

- START

When placed in any position other than OFF, the ignition switch provides fused battery voltage inputs to the Body Control Module (BCM). When placed in the START position, the ignition switch also provides fused battery voltage input to the PCM. The ignition switch contains a key-in-ignition input that allows the BCM (Body Control Module) to detect when the key has been inserted in the ignition to initiate the module wake up cycle. This information is also used by the BCM (Body Control Module) for the brake shift interlock system. For information on the brake shift interlock system, refer to Automatic Transmission/Transaxle.

Key Removal Inhibit Solenoid

The key removal inhibit solenoid (also known as the key release interlock actuator) is an electronically controlled solenoid that prevents the ignition lock cylinder from being turned to the OFF position unless the gear selector lever is in the PARK position. The key removal inhibit solenoid is part of the ignition switch.

Steering Column Control Module (SCCM)

The Steering Column Control Module (SCCM) controls various systems and/or features:

- Wiper and washer system, refer to Wiper And Washer Systems.

- Exterior lighting, refer to Lighting and Horns.

- Interior lighting, refer to Lighting and Horns.

- Steering wheel audio controls (if equipped), refer to Accessories and Optional Equipment.

- Steering wheel message center controls (if equipped), refer to Instrument Panel, Gauges and Warning Indicators.

- Cruise control, refer to Fire Suppression System.

- Adjustable pedals, refer to Hydraulic System, Brakes &/or Brake Pedal Assy.

- Steering column control, refer to Steering Column.

The SCCM (Steering Column Control Module) also provides a pass-through circuit path for various components and/or features:

- Steering wheel switch illumination

- Driver air bag module

- Horn

The multifunction switch, brake pedal control switch (if equipped), hazard flasher switch, steering column control switch (if equipped), and LH/RH steering wheel switches (if equipped) provide inputs to the SCCM (Steering Column Control Module). Based on inputs from the various switches, the SCCM (Steering Column Control Module) communicates over the High Speed Controller Area Network (HS-CAN) or the Local Interconnect Network (LIN) to control the supporting features.

Clockspring

The clockspring is mounted on the front of the SCCM (Steering Column Control Module) and provides a continuous electrical connection between the driver air bag and the Restraints Control Module (RCM) when the steering wheel is turned. For information on the clockspring and other components of the Supplemental Restraint System (SRS), refer to Restraints and Safety Systems &/or Air Bag Systems.

Steering Wheel Rotation Sensor

The steering wheel rotation sensor is mounted on the front of the SCCM (Steering Column Control Module) behind the clockspring and provides steering wheel position information to the SCCM (Steering Column Control Module). This information is broadcast over the HS-CAN (High Speed Controller Area Network).

Multifunction Switch

The multifunction switch is mounted directly to the SCCM (Steering Column Control Module) and controls the low/high-beam headlamps, flash-to-pass, turn signals, windshield wiper and washer and front camera washer (if equipped), by transferring the driver inputs to the SCCM (Steering Column Control Module). The high-beam headlamps, flash-to-pass and turn signals are communicated from the SCCM (Steering Column Control Module) over the HS-CAN (High Speed Controller Area Network). The windshield wiper and front camera washer signals (if equipped) are communicated from the SCCM (Steering Column Control Module) to the wiper motor internal module over the LIN (Local Interconnect Network). When the BCM (Body Control Module) receives the correct signal from the SCCM (Steering Column Control Module), the BCM (Body Control Module) activates the required component.

Brake Pedal Control Switch

The brake pedal control switch is mounted directly to the SCCM (Steering Column Control Module) and controls the forward and rearward movement of the accelerator and brake pedals. The brake pedal control switch functions when the ignition switch is in the OFF, ACC or RUN positions. When the brake pedal control switch is pressed voltage is connected through the SCCM (Steering Column Control Module) to the adjustable pedals motor.

Hazard Flasher Switch

The hazard flasher switch is mounted directly to the SCCM (Steering Column Control Module) and operates when the ignition switch is in any position or when the key is removed. One press of the switch supplies a ground signal through the SCCM (Steering Column Control Module) to the BCM (Body Control Module). When the ground signal is sensed by the BCM (Body Control Module) it turns the directional indicators ON. A second press of the button releases the ground connection and turns the directional indicators OFF.

Steering Wheel Switches

The steering wheel switches are mounted directly to the steering wheel and wired to the SCCM (Steering Column Control Module). Depending on what features the vehicle is equipped with, the SCCM (Steering Column Control Module) sends messages via the HS-CAN (High Speed Controller Area Network) to the PCM (cruise control), Instrument Panel Cluster (IPC) (message center) and BCM (Body Control Module) (entertainment system). The SCCM (Steering Column Control Module) entertainment system messages are received by the BCM (Body Control Module) via HS-CAN (High Speed Controller Area Network) and gatewayed over the Medium Speed Controller Area Network (MS-CAN) where the messages are received by the applicable entertainment system module(s).