Conventional Cruise Control: Notes

DESCRIPTION 

Courtesy of CHRYSLER GROUP, LLC

The Conventional Cruise Control system is comprised of the following components:

The vehicle operator controls all of the conventional Cruise Control system features through the CSWC on the face of the right horizontal spoke of the steering wheel.

OPERATION 

• The driver of the vehicle presses any of the cruise control specific buttons
• The cruise control switch transits the request over the Local Interconnect Network (LIN) bus to the SCCM
• The SCCM transmits this information over the Controller Area Network-Chassis (CAN-C) bus to the PCM
• The PCM manages the algorithm in order to keep the vehicle speed set by the driver

The Cruise Control system automatically disables when:

• Brake pedal pressed
• Cruise Control CANCEL button pressed
• Engine Revolutions Per Minute (RPM) are too high
• Electronic Park Brake (EPB) engaged
• Brake pedal fault detected
• Transmission enter Limp Mode
• Electronic Stability Control (ESC) active or a ESC fault is detected
• TCM reports ATX that the shifter is not in D  rive
• The ignition state changes to OFF
• The DTCM reports that 4LO is engaged

The PCM monitors for these conditions and will send a Controller Area Network-Chassis (CAN-C) signal to the IPC to display the appropriate indication to the vehicle operator.

Active Speed Limiter

Active Speed Limiter is a function that allows the driver to set the vehicle speed limit. This function is set by the driver by interfacing with the CSWC button interface. The limiter function is active when the speed of the vehicle is equal to the limitation set point designated by the driver. If the driver exceeds this designated set point, the driver will be warned through audio and visual messages on the IPC. The driver is able to override the limiter function by pressing the accelerator pedal to speed the vehicle beyond the designated set point.

It is important to note that any vehicle driving system utilizing active torque requests (such as braking, traction, or stability events) will take precedence over and inhibit the active speed limiter and Cruise Control functions. Active speed limiting and Cruise Control will operate again once the torque request has been honored.

Active speed limiter and Hill Descent Control (HDC) are mutually exclusive and can not be active at the same time.

Cruise Control Button Functions:

• ON/OFF  - This is a momentary button used to activate and deactivate the system. If the Active Speed Limiter is turned ON, the first pulse will turn OFF the Active Speed Limiter, the second pulse will turn ON the Cruise Control.
• SET/- 

  - This is a momentary button used to command three different functions according to the push activation mode and Cruise Control state: set, decelerate and tap-down:

  • Set 

    - When Cruise Control is not regulating the vehicle speed, but is able to receive commands and the vehicle current speed is valid, a pulse or continuous activation of this button, causes the following actions:

    • The vehicle speed is stored at the instant of button activation.
    • The Cruise Control becomes active and the vehicle speed is under regulation.
  • Decelerate  - When Cruise Control is already "Active", a continuous activation of the button will decrease the speed set target with pre-arranged, adjustable gradient until the minimum value allowed. When the button is released, the system stores the new speed reached by the vehicle.
  • Tap Down  - When Cruise Control is already "Active", a pulse activation of the button will decrease the speed set point of a constant adjustable step until the minimum value allowed. When the button is released, the system stores the new speed value.

  This function will not be activated if the current vehicle speed is not valid.

• SET/+ 

  - This is a momentary button used to command three different functions according to the push activation mode and Cruise Control state: set, acceleration and tap-up.

  • Set 

    - When Cruise Control is not regulating the vehicle speed, but is able to receive commands and the vehicle current speed is valid, a pulse or continuous activation of this button, causes the following actions:

    • The vehicle speed is stored at the instant of button activation.
    • The Cruise Control becomes active and the vehicle speed is under regulation.
  • Acceleration  - When Cruise Control is already "Active", a continuous activation of the button will increase the speed set target with pre-arranged, adjustable gradient until the maximum value allowed. When the button is released, the system stores the new speed reached by the vehicle.
  • Tap Up  - When Cruise Control is already "Active", a pulse activation of the button will increase the speed set point of a constant adjustable step until the maximum value allowed. When the button is released, the system stores the new speed value.
• RESUME  - This is a momentary switch that allows the Cruise Control to be re-engaged to the last stored vehicle speed, provided that the Cruise Control system is still enabled and current vehicle speed is greater then the calibrated minimum resume speed.
• CANCEL  - This is a momentary switch that places the Cruise Control in a disengaged state, but keeps the system enabled and set speed stored.