Conventional Speed Control

WARNING: This page is about a different car, the 2016 Dodge Charger and 2015 Dodge Charger. However, it is still accessible from the selected car via links, so may be relevant.

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. The Steering Column Control Module (SCCM) reads the speed control switch input via LIN bus. The SCCM relays an electronic speed control switch status message to the Powertrain Control Module (PCM) over the Controller Area Network (CAN) data bus (CAN-C). The PCM software continually monitors these inputs as well as electronic vehicle distance message inputs from the Antilock Brake System Module (ABS) and numerous hard wired inputs including the brake (stop) lamp sensor, then provides the appropriate electronic message and hard wired outputs to invoke the requested electronic speed control features. The PCM manages the Cruise Control algorithm to maintain vehicle speed established by the driver. It is also the responsibility of the PCM to send out cruise control override information and perform stuck button diagnostics.

The PCM microcontroller 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) (also known as the Check Engine lamp) in the Instrument Cluster (IC) and for system diagnosis and testing through the 16-way data link connector located on the driver side lower edge of the instrument panel.

The hard wired inputs and outputs for the PCM may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. However, conventional diagnostic methods will not prove conclusive in the diagnosis of the PCM or the electronic controls or communication between other modules and devices that provide features of the conventional speed control system. The most reliable, efficient, and accurate means to diagnose the PCM or the electronic controls and communication related to speed control system operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.