Description And Operation: Adaptive: Operation

WARNING: This page is about a different car, the 2022 Chrysler Voyager and 2022 Chrysler Pacifica. However, it is still accessible from the selected car via links, so may be relevant.

The vehicle operator controls all ACC 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 a Local Interface Network (LIN) switch input to the SCCM.
The SCCM reads the speed control switch input, then relays an electronic speed control switch status message to the PCM and to the ACC module over the Controller Area Network (CAN) data bus.
The PCM and LRR continually monitor these inputs as well as electronic wheel speed message inputs from the ABS module, electronic gear selector message inputs from the TCM, and numerous hard wired inputs including the stop lamp sensor, then provides the appropriate electronic message and hard wired outputs to invoke the requested electronic speed control features.

Using the MODE push button of the speed control switch pod on the face of the right horizontal spoke of the steering wheel, the vehicle operator can choose between adaptive speed control and conventional speed control modes of operation. As the name implies, when in the conventional speed control mode the speed control system is used and functions exactly like a conventional speed control system. When in the adaptive speed control mode, the vehicle operator can use the DISTANCE increase or decrease push buttons of the speed control switch pod to select from one of three distance settings for the adaptive cruise system to maintain. These settings equate to the time in seconds separating the vehicle from a preceding vehicle. The LRR sends electronic message outputs to the ABS, the TCM and the PCM to maintain the selected separation distance. The available distance settings are:

1 - 1.0 second
2 - 1.2 second
3 - 1.5 seconds
4 - 2.0 seconds

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

Engine Speed Sensor
Sensor or actuators of the electric throttle (only for gasoline engines)
Accelerator Pedal Potentiometer (APP Sensor)
Brake Pedal Position
Engine Load sensor
Ignition Coils
Fuel Injectors

The PCM and LRR continuously monitor all of the speed control system electrical circuits to determine the system readiness and accuracy. If the PCM or LRR detects a monitored system fault, it sets and stores a Diagnostic Trouble Code (DTC). The PCM and ACC components use 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.