Module, Steering Column Control (SCCM): Description
The Steering Column Control Module (SCCM) (2) is located near the top of the steering column directly below the steering wheel. The SCCM includes the left (lighting) multifunction switch (1), the right (wiper) multifunction switch (3), the clockspring (4) and an integral internal microcontroller. The SCCM microcontroller is a Local Interface Network (LIN) master node and a gateway to the Controller Area Network (CAN) data bus. For additional information on the clockspring. Refer to CLOCKSPRING, DESCRIPTION . For additional information on the left multifunction switch. Refer to SWITCH, MULTIFUNCTION, DESCRIPTION . For additional information on the right multifunction switch. Refer to SWITCH, MULTIFUNCTION, RIGHT, DESCRIPTION .
The SCCM housing is aligned on the steering column jacket by a rib integral to the upper steering column housing that is engaged in a groove in the mounting flange of the SCCM housing. A plastic latch feature of the SCCM mounting flange then snaps over a small lug that is also integral to the outer circumference of the upper steering column housing. A metal band clamp with a single screw tightens the flange to the steering column.
There are lugs cast into the outer circumference of the steering wheel hub that engage the inner circumference of the clockspring rotor hub to drive the clockspring and to disengage a small white plastic spring-loaded blocker that locks the clockspring rotor hub to the clockspring housing until the steering wheel is properly installed. The steering wheel hub disengages the blocker when properly installed. The steering wheel must be tightened to specification to ensure proper clockspring function.
The SCCM includes two integral connectors that face toward the instrument panel. The terminal pins that populate one connector are integral to the clockspring and are connected to the vehicle electrical system through a take out and connector of the instrument panel wire harness. The SCCM housing also has an internal interconnect receptacle that faces toward the steering wheel. This receptacle accepts the fixed terminal pins of the clockspring half of the interconnect, which consists of several circuits that pass through the clockspring dedicated to connecting the SCCM microcontroller unit to the vehicle electrical system.
The SCCM housing, the clockspring, the multifunction switches as well as the SCCM microcontroller electronics unit cannot be adjusted or repaired. If ineffective or damaged the entire SCCM housing, clockspring, left multifunction switch, right multifunction switch and microcontroller must be replaced as a unit.