ACC Operation

NOTE: For a complete illustration of the ACC indicators and graphic displays, refer to the Owner's Literature.

The ACC system functions much like a standard cruise control system. The ACC system automatically adjusts the vehicle speed to maintain a set distance gap from the front of the vehicle and the vehicle in the same path of travel. When the ACC system is on and is following a vehicle or a vehicle enters the same driving lane, a follow vehicle graphic is displayed in the message center.

The ACC system does not function if the vehicle speed is below 20 km/h (12 mph). As the vehicle slows down during automatic braking, the ACC system discontinues braking at 20 km/h (12 mph). At that speed, an audible alarm sounds and the automatic braking from the ABS module is released. The driver must take over the vehicle braking control.

The cruise control deactivator switch (which is integral to the BPP switch) is an additional safety feature. When the brake pedal is applied, the cruise control system deactivator switch opens and removes the ground signal from the PCM input circuit, releasing the throttle and immediately deactivating the system.

The CCM monitors the yaw rate signal from the ABS module and compares it to the wheel speed and steering wheel angle signals. If the ABS module determines the yaw rate is invalid, the CCM disables the ACC. The message center displays the message COLLISION WARNING MALFUNCTION and/or ADAPTIVE CRUISE MALFUNCTION.

The CCM monitors the environment in front of the vehicle while active. If the radar beam is obstructed by a buildup of snow, ice, rain or other debris or the vehicle is driven in a desert environment with no other traffic for extended periods of time, the sensor will trigger an "ADAPTIVE CRUISE NOT AVAILABLE SENSOR BLOCKED SEE MANUAL" message in the message center and will disable the ACC. The ACC resumes once the obstruction is cleared and the radar is able to detect targets or upon a key cycle.

The ACC system does not engage properly if the front radar sensor is not aligned correctly and the message center will display FRONT SENSOR NOT ALIGNED. The ACC resumes once the radar is aligned and is able to properly detect targets.

The CCM radar vertical and horizontal alignment procedure is located in General Procedures. The horizontal alignment for the CCM is a calibration check performed by the scan tool to insure the CCM radar is pointed straight. The scan tool identifies this as, Alignment Offset with a horizontal specification of +/- 3.0 degrees offset. For additional information, Refer to: Cruise Control Radar Alignment .

The ABS module estimates brake temperature by monitoring applied brake pressure over a period of time and sends a message to the CCM when the estimated temperature is above a given threshold. An alarm sounds and the ACC system is deactivated until the estimated brake temperature returns to cooler operating conditions. This condition can happen in a hilly or mountainous driving terrain.