Cruise Control - With Adaptive Cruise Control

The adaptive cruise control system functions much like the standard cruise control system. The adaptive cruise control system automatically adjusts the vehicle speed to maintain a set gap distance from the front of the vehicle and the vehicle in the same path of travel.

The adaptive cruise control steering wheel mounted switches are momentary contact switches that toggle up and down for the cruise control switch state. The adaptive cruise control switch inputs are networked over the High Speed Controller Area Network (HS-CAN) from the Steering Column Control Module (SCCM) to the PCM to control the adaptive cruise control system. Pressing and releasing the steering wheel cruise control ON/OFF switch turns the cruise control system on. The adaptive cruise control indicator located in the IPC  illuminates gray and the previous gap setting and SET graphic is displayed indicating the system is in standby mode. This notifies the driver that the system is ready and the vehicle can be accelerated to the desired speed. Pressing up (SET+) and releasing the SET switch sets the vehicle's speed and stores the set speed in memory. The adaptive cruise control indicator illuminates green and the message center displays the set speed and gap setting graphic.

There are 2 ways to change the set speed. The first way is to accelerate or brake to the desired speed and press and release the SET cruise control switch until the desired set speed is shown on the message center. The second way is by tapping the SET+ or the SET- switch while in the set mode, increasing or decreasing the displayed set speed by 1.6 km/h (1 mph) per tap. If the respective button is pressed and held, the displayed set speed continues to increase or decrease until the button is released. The adaptive cruise control system may apply the brakes to slow the vehicle down to the new set speed. The set speed displays continuously in the message center while the adaptive cruise control system is active.

When the adaptive cruise control system is on and is following a vehicle ahead or a vehicle enters the same driving lane, a follow vehicle graphic is displayed in the message center.

When a vehicle ahead enters the same lane or a slower vehicle is ahead in the same lane, the vehicle speed adjusts automatically to maintain a preset distance gap. A bar graph graphic with 4 preset distance gap settings are displayed in the message center. Pressing up (decrease) or down (increase) on the steering wheel cruise control gap switch increases or decreases the distance from the vehicle ahead. If all of the bars are illuminated, this is the longest gap setting. If only one bar is illuminated that is the shortest gap setting.

After each ignition cycle, the previous gap setting is remembered and the system is set to that gap setting.

The distance gap can be overridden by pressing the accelerator pedal. The follow vehicle graphic is not displayed in the message center and the GAP and set speed display turns gray. When the accelerator is released, the adaptive cruise control system returns to normal operation and the vehicle speed decreases to the set speed or a lower speed if following a vehicle ahead.

For a complete illustration of the adaptive cruise control indicators and graphic displays refer to the Owner's Literature.

The vehicle maintains the distance gap to the vehicle ahead until:

• the vehicle ahead accelerates to a speed above the set speed.
• the vehicle ahead moves out of the lane or out of view.
• the vehicle speed falls below 30 km/h (18 mph).
• a new gap distance is set.

The Cruise-Control Module (C-CM) contains a radar sensor unit that determines the distance and relative speed of the vehicle that is in the path of travel. The C-CM  commands the ABS module, which controls the brakes, to automatically apply the brakes to slow the vehicle to maintain a safe distance to the vehicle in front. The ABS module sends a network message to the Body Control Module (BCM) that an electronically controlled deceleration has occurred. The BCM  sends a voltage signal to illuminate the stoplamps. The C-CM  , ABS module, and the BCM  communicate over the High Speed Controller Area Network (HS-CAN).

The ABS module monitors the yaw rate signal from the Restraints Control Module (RCM) over the HS-CAN  and compares it to the wheel speed and steering wheel angle signals. If the ABS module determines the yaw rate is invalid, the ABS module disables the adaptive cruise control. The message center displays the message COLLISION WARNING MALFUNCTION and/or ADAPTIVE CRUISE MALFUNCTION.

The vehicle is equipped with a collision avoidance system that uses the C-CM  radar sensor to detect vehicles ahead that are moving in the same direction as the vehicle with adaptive cruise control system. In the event of a collision risk, the driver is alerted by a series of red LED warning lights which is part of the Head Up Display (HUD) module, and an audible warning chime. For more information on the collision avoidance system, refer to COLLISION AVOIDANCE . The maximum braking applied by the adaptive cruise control system is limited and can be overridden by the driver applying the brakes. If the adaptive cruise control system determines that its maximum braking level will not be sufficient to slow the vehicle and avoid collision, the Head Up Display (HUD) module flashes and an audible warning tone sounds while the system continues to brake. The driver must then take over the vehicle braking control.

Pressing and releasing the OFF switch, or switching the ignition to OFF, turns the adaptive cruise control system off. The adaptive cruise control set speed memory is erased.

Pressing the brake pedal or pressing the RES/CNCL switch puts the adaptive cruise control system in standby mode and the last set speed is displayed in the message center with a strike through. Pressing the RES/CNCL button when the adaptive cruise control system is in standby mode causes the vehicle to accelerate to the last set speed. The set speed continuously displays in the message center while the adaptive cruise control system is active. The RES/CNCL button does not function if the OFF button is pressed, the ignition is cycled OFF, or if the current vehicle speed is below the minimum operational speed.

The cruise control deactivator switch (which is integral to the stoplamp switch) is an additional safety feature. When the brake pedal is pressed, an electrical signal is sent from the stoplamp switch to the PCM deactivating the cruise control system. Under increased brake pedal effort, the cruise control deactivator switch opens and removes the ground signal from the PCM input circuit, releasing the throttle immediately deactivating the system.

The adaptive cruise control system does not function if the vehicle speed is below 30 km/h (18 mph). As the vehicle slows down during automatic braking, the adaptive cruise control system discontinues braking at 30 km/h (18 mph). At that speed, an audible alarm sounds and the automatic braking from the ABS module is released. The message CRUISE CONTROL [AUTOMATIC BRAKING TURNED OFF] is displayed in the message center. The driver must take over the vehicle braking control.

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

There are several conditions that can exist to cause the adaptive cruise control system to deactivate or prevent the system from activation. Some of the conditions have a message that is displayed in the message center. These conditions include:

If the C-CM  radar or front bumper cover is dirty or obstructed due to rainy or snowy conditions, the message center displays ADAPTIVE CRUISE SENSOR BLOCKED. Clean the surface of the radar and bumper fascia cover of any debris, moisture, snow, ice or obstruction.