Description And Operation: Conventional: Operation

• The vehicle operator controls all conventional speed control system features through the speed control switch pod on the face of the right horizontal spoke of the steering wheel.
• When a push button of the switch pod is depressed, it provides an input to the SCCM.
• The SCCM reads the speed control switch input via Local Interface Network (LIN), then relays an electronic speed control switch  status message to the PCM over the Controller Area Network-Chassis (CAN-C) network.
• The PCM software continually monitors these inputs as well as electronic vehicle speed  message inputs from the ABS module and numerous hard wired inputs including the brake (or stop) lamp switch, then provides the appropriate electronic message and hard wired outputs to invoke the requested electronic speed control features.

The PCM continuously monitors all of the speed control system electrical circuits to determine the system readiness. If the PCM detects a monitored system fault, it sets and stores a Diagnostic Trouble Code (DTC). The PCM uses On-Board Diagnostics (OBD) and can communicate with other electronic modules in the vehicle as well as with the diagnostic scan tool using the CAN data bus. This method of communication is used for control of the Malfunction Indicator Lamp (MIL) in the IPC and for system diagnosis and testing through the data link connector located on the driver side lower edge of the instrument panel.

If the PCM detects a fault on one of the following systems, it will disable the cruise control system. The PCM will store an appropriate DTC.

• Engine Speed Sensor
• Accelerator Pedal Potentiometer (APP) Sensor
• Brake Pedal Position
• Engine Load sensor
• Ignition Coils
• Fuel Injectors

The hard wired inputs and outputs for the PCM may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information.