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Speed Control - With Adaptive Cruise Control

NOTE: The speed control sensor is also known as the forward looking sensor.

Pressing and releasing the steering wheel speed control ON switch turns the speed control system on. The message center displays the message CRUISE ON RADAR READY. This notifies the driver that the system is ready and the vehicle can be accelerated to the desired speed. Pressing and releasing the SET+ switch, sets the vehicle's speed that will be stored in memory and the message center displays SET XXX MPH (XXX km/h).

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+ or SET- speed 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 maintained vehicle speed by 1.6 km/h (1 mph) per tap. If the respective button is pressed and held, the vehicle speed continues to accelerate or decelerate 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.

The green speed control indicator illuminates in the IPC  if the adaptive cruise control is on and is not following a vehicle ahead, while the amber adaptive cruise control indicator illuminates in the IPC  if the adaptive cruise control is on and is following a vehicle ahead or a vehicle enters the same driving lane.

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. Pressing the steering wheel speed control gap switch (<--->), the distance can be decreased or increased from the vehicle ahead. There are 3 gap settings that display on the message center:

After each ignition cycle, the default gap setting is set to GAP <----->, which is the largest distance gap from the vehicle ahead. The message center momentarily displays the preset gap each time the distance gap is set.

The distance gap can be overridden by pressing the accelerator pedal. The green speed control indicator illuminates in the IPC  and the message CRUISE OVERRIDE displays in the message center. 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.

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

The speed control sensor, which is a radar unit, determines the distance and relative speed of the vehicle that is in the path of travel. The Cruise-Control Module (C-CM) commands the ABS module, which controls the vehicle brakes, to automatically apply the brakes to slow the vehicle to maintain a safe distance to the vehicle in front. The C-CM  communicates with the ABS module over the High Speed Controller Area Network (HS-CAN). The C-CM  monitors the yaw rate signal from the ABS module and compares it to the yaw rate signal from the speed control sensor. The maximum braking, which is 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, then an audible warning tone sounds while the system continues to brake. The message center displays DRIVER INTERVENE, and the driver should take immediate action.

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

Pressing the brake pedal puts the adaptive cruise control system in the standby mode. Pressing the RESUME button, when the adaptive cruise control system is in the 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 RESUME button does not function if the OFF button is pressed, the ignition switch is in the OFF position, or if the current vehicle speed is below the minimum operational speed.

The speed control deactivator switch is provided as an additional safety feature. When the brake pedal is pressed, an electrical signal is sent from the stoplamp switch to the PCM, then the PCM deactivates the speed control system. Under increased brake pedal effort, the deactivator switch opens and removes the voltage from the PCM input circuit, releasing the throttle.

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 DRIVER INTERVENE message displays in the message center. The automatic braking from the ABS module is released and 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. This condition may happen in a hilly or mountainous driving terrain.

There are several conditions that might 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:

MESSAGE DISPLAY CHART

Conditions Message
The speed control sensor is blocked (CRUISE RADAR BLOCKED)
The brake temperature is high due to hilly conditions (CRUISE NOT AVAILABLE)
A failure has occurred in the adaptive cruise control system (CRUISE MALFUNCTION)
A failure in the PCM or a failure in the ABS (CRUISE NOT AVAILABLE)
Speed control switch is stuck or faulty No message is displayed
Stoplamp switch is faulty No message is displayed

If the speed control sensor or fascia cover is dirty or obstructed due to rainy or snowy conditions, the message center displays CRUISE RADAR BLOCKED. The surface of the radar and speed control sensor fascia cover should be cleaned of any debris, moisture, snow, ice or any obstruction.