Object Detection System: Overview Cadillac SRX II facelift

Circuit/System Description

The B218L Side Object Sensor Module - Left or B218R Side Object Sensor Module - Right can set this code if the module determines there is a fault due to the reason listed in the symptom byte.

B218R Side Object Sensor Module - Right communicates on a private communication data bus with the B218L Side Object Sensor Module - Left. The B218L Side Object Sensor Module - Left is the master and can set this code if the B218R Side Object Sensor Module - Right determines it has an internal fault. DTC U18A6 will set if the left module is unable to communicate with the right side module.

The side blind zone alert system sensors are located behind the rear fascia and detect and report objects on either side of the vehicle, within a specified blind zone. The system alerts with a visual indicator placed on each side rear view mirror, to the presence of objects that may not be visible in the inside rearview mirror and outside rearview mirrors. When the system detects a vehicle in the side blind zone while driving forward, independent if passing a vehicle or being passed, an amber warning symbol will light up in the appropriate outside mirror. This indicates that it may be unsafe to change lanes. If the driver then activates the turn signal, the amber warning symbol starts flashing and a chime sounds to give an extra warning not to change lanes. The Side Object Sensor Module provides the voltage to the outside rearview mirror to illuminate the Side Blind Zone alert symbol on the mirror.

Side blind zone alert is active from speeds of 10 km/h (6.2 MPH) up to 140 km/h (87 MPH). Driving faster deactivates the system, indicated by low lighting warning symbols in the mirrors. Driving under this speed again will turn off the warning symbols. If then a vehicle is detected in blind zone, the warning symbols will illuminate normally on the appropriate side. When the vehicle is started, both outside mirror displays will briefly come on to indicate that the system is operating.

The object sensors are 3-wire sensors that are used to determine the distance between the vehicle and an object of interest. The front and rear parking assist control module supplies 8 V to the object sensors via the 8 V reference circuit and provides ground via the low reference circuit. The front and rear parking assist control module triggers the sensors in a sequential loop. After each sensor transmits, the front and rear parking assist control module uses the sensor echo received through the signal circuit to calculate the distance and position of an object.

The object sensors are 3-wire sensors that are used to determine the distance between the vehicle and an object of interest. The front and rear parking assist control module supplies 8 V to the object sensors via the 8 V reference circuit and provides ground via the low reference circuit. The front and rear parking assist control module triggers the sensors in a sequential loop. After each sensor transmits, the front and rear parking assist control module uses the sensor echo received through the signal circuit to calculate the distance and position of an object.

The parking assist can be enabled/disabled by pressing the parking assist switch. If the parking assist is enabled, engaging the reverse gear activates the parking assist feature. By subsequently pressing the parking assist switch the parking assist can be disabled.

The indicator in the parking assist switch shows the status of the parking assist. If the lamp is ON, parking assist is enabled.

For vehicles without UGN the indicator and switch are connected to the front and rear parking assist control module and the system operates as a stand-alone feature.

With UGN, the indicator and switch are connected to the active safety control module. The active safety control module received input from several modules including the park assist module to provide additional features. The park assist alerts and DTCs originate from the front and rear parking assist control module with the exception of the indicator DTCs which are set by the active safety control module. There are no switch DTCs for vehicles with the active safety control module.

The lane departure warning is enabled and disabled through the lane departure warning switch. When enabled, the frontview camera module will illuminate the indicator located in the switch. For the exact location of the lane departure warning switch, refer to the Owner's Manual.

For vehicles without UGN, the indicator and switch are connected to the frontview camera module and the system operates as a stand-alone feature.

With UGN, the indicator and switch are connected to the active safety control module. The active safety control module receives input from several modules including the frontview camera module to provide additional features. The lane departure alerts and DTCs are set by the frontview camera module with the exception of the indicator DTCs, which are set by the active safety control module. There are no switch DTCs for vehicles with the active safety control module.

The front view camera module permanently monitors the serial data bus for error messages. When a malfunction is detected by the front view camera module, the system will be disabled and an error message will be stored in the front view camera module disable history buffer which is used to store information about the front camera features that are disabled.

When the ignition is turned ON, the parking assist control module, frontview camera module, radar sensor modules and active safety control module receive the vehicle identification number (VIN) from the body control module. The modules will compare the VIN received to the VIN stored in memory.

The side detection system uses two modules B218L Side Object Sensor Module - Left and B218R Side Object Sensor Module - Right. The left module is the master and is on the vehicle's serial data bus and communicates to the right module on a private bus. The internal fault detection is handled inside the B218L Side Object Sensor Module - Left. No external circuit diagnosis is involved.

When the vehicle is placed in reverse with the engine running, a voltage signal is sent to the rearview camera to turn on and send a video signal to the Human Machine Interface Control Module. If the Human Machine Interface Control Module does not see a signal from the camera it will set B127B 2B and display "Service Rear Vision System".

The object sensors are 3-wire sensors that are used to determine the distance between the vehicle and an object of interest. The front and rear parking assist control module supplies 8 V to the object sensors via the object sensor supply voltage circuit and provides ground via the object sensor low reference circuit. The front and rear parking assist control module triggers the sensors in a sequential loop. After each sensor transmits, the front and rear parking assist control module uses the sensor echo received through the object sensor signal circuit to calculate the distance and position of an object.

The object sensors are 3-wire sensors that are used to determine the distance between the vehicle and an object of interest. The parking assist control module supplies 8 V to the object sensors via the object sensor supply voltage circuit and provides ground via the object sensor low reference circuit. The parking assist control module triggers the sensors in a sequential loop. After each sensor transmits, the parking assist control module uses the sensor echo received through the object sensor signal circuit to calculate the distance and position of an object.

The haptic seats, also known as Active Safety Seats, provide a vibration to alert the driver in certain circumstances. There are two motors in the driver's seat cushion. Either the right or left motor can run or both depending on the alert. The K40D Seat Memory Control Module - Driver provides the output voltage for the motors. The K40D Seat Memory Control Module - Driver receives serial data requests from other modules to activate the appropriate seat motors with the number of pulses requested. While the motors are activated, the K40D Seat Memory Control Module - Driver checks for either shorts to voltage or shorts to ground. Due to the nature of the PWM signal, if a motor circuit is open, it may be reported as either a short to voltage or short to ground.

The lane departure warning system is controlled by the Frontview Camera Module mounted on the windshield. Lane departure warning is enabled and disabled through a switch located in the instrument panel. When enabled, the Frontview Camera Module will illuminate the indicator located in the switch.

When the system is operating and can detect the lane markings, the Frontview Camera Module will request via serial data communications that the instrument panel cluster illuminate the green lane departure ready-to-assist indicator. If the Frontview Camera Module detects that the vehicle has crossed a lane marking without the turn signal being used, the module will request that the Instrument Cluster flash the yellow lane departure warning indicator. An audible warning will also sound three times when the yellow Instrument Cluster indicator is flashing.

The B233 Radar Sensor Module - Short Range can set this code if it determines there is a fault due to the reason listed in the symptom byte.

The B233B Radar Sensor Module - Long Range could not auto align properly as a result of the module being out of position. After alignment calibration process has begun, the B233B Radar Sensor Module - Long Range will attempt to align itself for approximately 30 minutes of driving time.

The frontview camera module has determined that it is not properly mounted.

The active safety control module is constantly sending a serial data message to the engine control module requesting engine speed or torque reduction. The engine control module sets DTC P15F6 when it detects a discrepancy in the structure of the message causing the integrity of the message to be questioned. An intermittent fault in the serial data circuits will cause the engine control module to set DTC P15F6.

The haptic seats, also known as Active Safety Seats, provide a vibration to alert the driver in certain circumstances. There are two motors in the driver's seat cushion. Either the right or left motor can run or both depending on the alert. The K40D Seat Memory Control Module - Driver provides the output voltage for the motors. The K40D Seat Memory Control Module - Driver receives serial data requests from other modules to activate the appropriate seat motors with the number of pulses requested. While the motors are activated, the K40D Seat Memory Control Module - Driver checks for either shorts to voltage or shorts to ground. Due to the nature of the PWM signal, if a motor circuit is open, it may be reported as either a short to voltage or short to ground.

The forward collision alert system is controlled by the frontview camera module mounted on the windshield. The system is designed to detect vehicles directly ahead, within a distance of approximately 60 meters (197 ft). The forward collision alert system operates at speeds above 40 km/h (25 mph). When the system detects a vehicle in the path ahead, the green vehicle ahead alert indicator in the driver information center is illuminated. When approaching another vehicle too rapidly, the collision alert symbol will flash and the radio will beep or the haptic seat will pulse, depending on user configuration. The red collision alert display will stay continuously illuminated if the vehicle ahead remains much too close. These actions are requested by the frontview camera module via serial data. The forward collision alert switch is part of the left steering wheel controls and is used to adjust the timing sensitivity of the front collision alert system.

The parking assist system is enabled and disabled through the parking assist switch. When enabled, the parking assist indicator will illuminate.

For vehicles without UGN, the switch and indicator are connected to the Parking Assist Control Module. The Parking Assist Control Module supplies a reference voltage to the parking assist switch. When the switch is pressed, the signal circuit is grounded. The Parking Assist Control Module can control the Park Assist Indicator by grounding the control circuit to illuminate the LED which indicates that the system is enabled.

With UGN, the indicator and switch are connected to the Active Safety Control Module. The Active Safety Control Module receives input from several modules including the Parking Assist Control Module to provide additional features. Refer to Object Detection Description and Operation (with Active Safety System, UGN, N America) , Object Detection Description and Operation (with Front and Rear Park Assist, UD5) , Object Detection Description and Operation (with Rear Park Assist, UD7) , Object Detection Description and Operation (with Side Blind Zone Alert, UFT, N America) , Object Detection Description and Operation (with Rear Cross Traffic Alert, UFG, N America) , Object Detection Description and Operation (with Forward Collision Alert, UEU) , Object Detection Description and Operation (with Lane Departure Warning, UFL) , Object Detection Description and Operation (with Haptic Signal Motor Seat) , Object Detection Description and Operation (with Adaptive Cruise Control, KSG, N America) , Object Detection Description and Operation (with Active Safety System, UGN, except N America) , Object Detection Description and Operation (with Adaptive Cruise Control, KSG, except N America) , Object Detection Description and Operation (with Side Blind Zone Alert, UFT, Except N America) , Object Detection Description and Operation (with Rear Cross Traffic Alert, UFT, Except N America) for additional information on UGN. A malfunction in with the UGN system may also disable parking assist. The parking assist alerts and DTCs are from the Parking Assist Control Module with the exception of the indicator DTCs which are sent by the Active Safety Control Module. There are no switch DTCs for vehicles with the Active Safety Control Module.

The Parking Assist Control Module supplies an 8V reference voltage and a low reference to the object sensors. The sensors will return a signal based on the reflections from objects within range of the sensors.

When an object is detected, the Parking Assist Control Module will send serial data to the radio and memory seat module to provide either an audible alert or haptic feedback through the Active Safety Seat. The driver can select between audible or haptic alerts in the vehicle personalization menu.

The side object sensor modules are located on each side of the vehicle behind the rear fascia and are not directly visible from outside the vehicle. The same sensors are also used for side blind zone alert. The sensors use radar to determine the presence of objects near the back of the vehicle. When an object is detected in the rear cross traffic zone, the module will send out a signal through serial data communication to turn on the visual icons and also audio chime or haptic notification. Each sensor is supplied B+ and ground. The right sensor receives an additional ground. Both sensors communicate independently on the serial data line. The serial data enters the left sensor in a pass-thru configuration, that connects to the right sensor. The scan tool is able to individually communicate with each sensor.

When the transmission is placed into REVERSE, a 12 V signal is sent to the B87 Rearview Camera indicating that camera operation is requested. Ignition voltage and ground are supplied to the rearview camera. The rearview camera sends video information to the K74 Human Interface Control Module through a video signal + and a video signal - circuit. A grounded shielding also wraps the video signal circuits to reduce electronic interference which may degrade the video signal and cause a distorted or otherwise degraded image.

The side object sensor modules are provided B+ and ground. The right side module has two grounds that distinguish it from the left side. Both modules are connected to serial data. The serial data line passes through the left module, therefore if the left module is disconnected, the right module will not be able to communicate. When an object is sensed by one of the sensors, it will supply voltage to the appropriate outside rearview mirror to illuminate the warning indicator. Ground is provided by the mirror through the door harness.

Side blind zone alert is active when the vehicle is out of park or the parking brake is off on manual transmission vehicles and at speeds up to approximately 140 km/h (87 MPH). If a vehicle is detected in the blind zone, the warning symbols will turn illuminate on the appropriate side. When the vehicle is started, both outside mirror displays will briefly come on to indicate that the system is operating. The warning symbols will vary brightness based on the ambient light conditions.

The side object sensor modules are located on each side of the vehicle behind the rear fascia and are not directly visible from outside the vehicle. The sensors use radar to determine the presence of objects nearby. The left side object sensor is the master that communicates on serial data. There is a private communication network between the left and right sensors. The scan tool can communicate only with the left sensor.

Side blind zone alert is active when the vehicle is out of park or the parking brake is off on manual transmission vehicles. If a vehicle is detected in the side blind zone, the warning symbols will turn illuminate on the appropriate side. The warning symbols will vary brightness based on the ambient light conditions.

When an object is detected in the left side blind zone, the side object sensor module sends a message to the right sensor through serial data. The right sensor then supplies voltage to illuminate the visual indicator on the left side outside rear view mirror. When an object is detected in the right side blind zone, the right side object sensor will supply a voltage to illuminate the visual indicator on the right side outside rear view mirror. Each sensor is supplied B+ and ground. Ground is provided through the outside rearview mirror harness.

The lane departure warning system is enabled and disabled through the lane departure switch. When enabled, the lane departure warning indicator will illuminate.

For vehicles without UGN, the switch and indicator are connected to the frontview camera module. The frontview camera module supplies a reference voltage to the lane departure switch. When the switch is pressed, the signal circuit is grounded. When enabled, the frontview camera module will illuminate the indicator located in the switch when lane departure warning system is enabled.

With UGN, the indicator and switch are connected to the active safety control module. The active safety control module receives input from several modules including the Parking Assist Control Module to provide additional features. The lane departure warning alerts and DTCs are from the frontview camera module with the exception of the indicator DTCs which are sent by the active safety control module. There are no switch DTCs for vehicles with the active safety control module.

When the system is operating and can detect the lane markings, the frontview camera module will request via serial data communications that the instrument cluster illuminate the green lane departure warning symbol. If the frontview camera module detects that the vehicle unintentionally crosses a lane marking without the turn signal being used, the module will request the instrument cluster to flash the amber lane departure warning indicator. An audible warning will also sound three times when the amber lane departure warning indicator in the instrument cluster is flashing.

Component Descriptions

Active Safety Control Module

The active safety control module analyzes data from various modules, sensors, and switches to provide enhanced safety features. In addition to providing alerts, the active safety control module will provide driver assistance through integrated brake assist, automatic collision preparation, rear emergency braking, and adaptive cruise control. Inputs and outputs can either be connected directly to the active safety control module or communicate though serial data. The active safety control module communicates on a dedicated object bus to all four radar sensor modules and the frontview camera module. A fault on the object bus may result in multiple DTCs since the active safety control module may not be able to communicate with some or all modules on the bus. See Data Link Communications Description and Operation for more serial data information.

Forward collision alert, lane departure warning, and park assist alerts can be user selected to either a haptic signal utilizing the driver's haptic signal motor seat or using beeps through the audio system. This setting can be found in the vehicle personalization menus. See the owner's manual for more detailed information on vehicle personalization. Refer to Object Detection Description and Operation (with Active Safety System, UGN, N America) , Object Detection Description and Operation (with Front and Rear Park Assist, UD5) , Object Detection Description and Operation (with Rear Park Assist, UD7) , Object Detection Description and Operation (with Side Blind Zone Alert, UFT, N America) , Object Detection Description and Operation (with Rear Cross Traffic Alert, UFG, N America) , Object Detection Description and Operation (with Forward Collision Alert, UEU) , Object Detection Description and Operation (with Lane Departure Warning, UFL) , Object Detection Description and Operation (with Haptic Signal Motor Seat) , Object Detection Description and Operation (with Adaptive Cruise Control, KSG, N America) , Object Detection Description and Operation (with Active Safety System, UGN, except N America) , Object Detection Description and Operation (with Adaptive Cruise Control, KSG, except N America) , Object Detection Description and Operation (with Side Blind Zone Alert, UFT, Except N America) , Object Detection Description and Operation (with Rear Cross Traffic Alert, UFT, Except N America) for more information on haptic signal motor seats.

If there is a DTC set in any of the modules that the active safety control module uses as inputs, it will send a "Service Driver Assist" to the instrument cluster to alert the driver of a problem with the system. No other specific details are given unless the driver attempts to activate a specific system. For example if the driver attempts to turn on lane departure warning, the instrument cluster will display "Lane Departure Unavailable" and the indictor will flash and then go out. A scan tool must be used to read the DTCs that are causing the malfunction to help find the problem. Some of the inputs to the active safety control module can affect forward facing features, rear facing features, or all features. Systems to check to determine which area to focus are rear park assist for rear features, and lane departure warning and adaptive cruise control for front features. If none of the active safety system features are operative, there may be an issue with another module on the vehicle not providing the proper data to the active safety control module. If all active safety control module features are inoperative, check the Adaptive Cruise Control Inhibit History and Disengage History scan tool data for the reason for the malfunction. Definitions of parameters and suggestions on what to look for can be found in Active Safety Control Module Scan Tool Information . Any item with a "Yes" was the reason why the adaptive cruise control system was inoperative at that time. In some cases verifying the module is the correct part number, has the latest version of software is necessary, and is calibrated properly.

1. Active Safety Control Module Inputs: EBCM Forward Collision Alert Switch Front and Rear Park Assist Module Frontview Camera Module Lane Departure Warning Switch Multi-axis Acceleration Sensor Park Assist Switch Radar Sensor Module - Long Range Radar Sensor Module - Short Range Left Front Radar Sensor Module - Short Range Right Front Radar Sensor Module - Short Range Rear Steering Wheel Angle Sensor Wheel Speed Sensors
2. Active Safety Control Module Outputs: BCM EBCM ECM Instrument Cluster (for alerts and heads up display if equipped) Lane Departure Warning Switch Indicator Memory Seat Module (for haptic seat alerts) ONSTAR Park Assist Switch Indicator Radio (for audio alerts) TCM

Forward Collision Alert Switch

The forward collision alert system can be adjusted to set the range of the warning by pressing the forward collision alert switch. The forward collision alert can be set to Far, Medium, Near, or Off. See owners manual for exact location of the forward collision alert switch. The forward collision alert switch is hard-wired to the body control module and is communicated to the active safety control module through serial data.

Front and Rear Park Assist Module

The front and rear park assist module uses ultrasonic object sensors located in the front and rear bumper fascia to provide distance measurements to nearby objects. The front and rear park assist module sends rear object data to the active safety control module on the Low Speed GMLAN.

Frontview Camera Module

The frontview camera module is located behind the windshield, looking out at the road ahead and detects lane markings and vehicles directly ahead, within a distance of approximately 60 meters (197 ft). The frontview camera module is used for lane departure warning and forward collision alert systems. The frontview camera module communicates on the object bus to the active safety control module.

Using information from the frontview camera module, the active safety control module will alert the driver to a vehicle ahead and provide forward collision alert and lane departure warnings. The alerts and warnings can be user-selected to be audible through the audio system or haptic using the active safety seat.

Lane Departure Warning Switch

The lane departure warning feature can be activated or deactivated by pressing the lane departure warning switch. See owners manual for exact location of the lane departure warning switch. The lane departure warning switch is hard-wired to the active safety control module. The switch contains a LED that is controlled by the active safety control module to indicate if lane departure warning feature is enabled.

Parking Assist Switch

Parking assist can be activated or deactivated by pressing the parking assist switch. See owners manual for exact location of the park assist switch. The parking assist switch is hard-wired to the active safety control module. The switch contains a LED that is controlled by the active safety control module to indicate if the parking assist feature is enabled.

Radar Sensor Module - Long Range

The radar sensor module - long range is located behind the front grille emblem and is used in the 30-200 meters (98-656 ft) range. The radar sensor module - long range communicates on the object bus to the active safety control module. In addition to the wiring harness ground, the module is grounded through the mounting bracket.

Radar Sensor Module - Short Range Left Front

The radar sensor module - short range left front is located behind the front bumper fascia and detects objects out to approximately 30 meters (98 ft). The radar sensor module - short range left front communicates on the object bus to the active safety control module.

Radar Sensor Module - Short Range Right Front

The radar sensor module - short range right front is located behind the front bumper fascia and detects objects out to approximately 30 meters (98 ft). The radar sensor module - short range right front communicates on the object bus to the active safety control module.

Radar Sensor Module - Short Range Rear

The radar sensor module - short range rear is located behind the rear bumper fascia and detects objects out to approximately 30 meters (98 ft). The radar sensor module - short range rear communicates on the object bus to the active safety control module. The radar sensor module - short range rear output data, along with the rear park assist output data, is used for rear emergency automatic braking.

Object Detection Description and Operation (with Front and Rear Park Assist, UD5)

The parking assist system is designed to identify and notify the driver of an object in the vehicle path when moving forward or reversing at speeds of less than 8 km/h (5 MPH). The distance and location of the object is determined by 8 object sensors: 4 located in the rear bumper and 4 located in the front bumper. The parking assist system will notify the driver using audible beeps through the radio or haptic pulses through the driver's seat. The driver can select between audible or haptic alerts in the vehicle personalization menus. See the user's manual for more detailed information on vehicle personalization.

The parking assist system is made up of the following components

1. Parking assist control module
2. Front object sensors
3. Rear object sensors
4. Parking assist switch
5. Parking assist indicator
6. Radio
7. Safety Alert Seat, if equipped.

Parking Assist Control Module

The parking assist control module provides a reference voltage and a low reference to the 8 object alarm sensors. The parking assist control module receives individual signals from each of the 8 sensors and determines the location and distance of an object based on these inputs. When an object is detected, the parking assist control module will send a data message via serial data to the radio requesting an audible alert.

Object Sensors

The object sensors are located in the front and rear bumpers of the vehicle. The sensors are used to determine the distance between an object and the bumper. Each sensor emits an ultrasonic frequency which is reflected off any object located in front of or behind the vehicle. These reflections are received by the sensors. The time difference between the emission of the frequency and when the reflection is received is known as sensor echo time, it is used to determine the distance to the object. The sensors report this information to the parking assist control module.

Parking Assist Switch

The parking assist can be activated and deactivated by pressing the parking assist switch. By engaging the reverse gear the parking assist can also be activated. By subsequently pressing the parking assist switch the parking assist can be disabled again.

Parking Assist Indicator

The indicator in the parking assist switch shows the status of the parking assist. If the lamp is ON, the parking assist is activated.

Radio

The radio controls the audible alert for the park assist alert. If the an object is detected the radio will command beeps as an audible alert to the driver.

Safety Alert Seat

The memory seat module controls the haptic alert provided by the seats. If an object is detected, the memory seat module will command pulses to the driver's seat.

Parking Assist Operation

When an object is within the measuring range of the sensor, the ultrasonic pulse is reflected and is received by the sending or a neighboring sensor. The sensor converts this signal into a voltage signal and sends this signal to the parking assist control module. The parking assist control module evaluates the received sensor signals. As soon as an object is within the measuring range, the parking assist control module sends a message via serial data to either the radio or seat module to provide an alert signal.

The parking assist system can detect objects greater than 7.6 cm (3 in) wide and 25.4 cm (10 in) tall. The system cannot detect objects below the bumper, underneath the vehicle. If an object is detected, one of the following will occur

1. The measuring range of the front object sensors is between 30-120 cm (11.8-47.2 in). From a distance of 120 cm (47.2 in), the acoustic signal is active. The frequency of the beep sound increases with decreasing distance. From a distance less than 30 cm (11.8 in), the sound becomes continuous.
2. The measuring range of the rear object sensors is between 30-250 cm (11.8-98.4 in). From a distance of 250 cm (98.4 in), the acoustic signal is active. The frequency of the beep sound increases with decreasing distance. From a distance less than 30 cm (11.8 in), the sound becomes continuous.

The parking assist can be activated and deactivated by pressing the parking assist switch. When REVERSE gear is selected, park assist automatically is engaged for both front and rear sensors. When the vehicle is put into DRIVE from REVERSE the front assist sensors will be active up to speeds of 8 km/h (5 MPH) to assist with parking maneuvers. Once the vehicle is above 8 km/h (5 MPH) the front sensors are disabled and will not be re-enabled until either REVERSE gear is selected or the parking assist switch is pressed to activate the system. Once the parking assist switch is pressed during a key cycle the front sensors become active at speeds under 8 km/h (5 MPH). If the park assist switch is pressed again in the same key cycle the message "Park Assist Off" will be displayed in the driver information center if the vehicle speed is under 8 km/h (5 MPH) and front sensors detect an object within 120 cm (47.2 in). The LED indicator on the parking assist switch provides the ON/OFF state of the system. If the indicator is ON, the system is active and ready to assist.

The parking assist control module carries out a self test and monitors the sensors for electrical and mechanical faults. Monitored is the power supply of each sensor and the sensor signals, which need to alter when the vehicle moves. If this is not the case, the sensor is acoustically blocked or faulty. Mud, ice and snow may cause obstruction of the function of the sensors. The parking assist control module also checks whether the correct type of sensor is installed. If any of these tests fails, a DTC with corresponding symptom is set, the parking assist is deactivated and the parking assist indicator in the instrument panel cluster is activated.

Object Detection Description and Operation (with Rear Park Assist, UD7)

The parking assist system is designed to identify and notify the driver of an object in the vehicle path when reversing at speeds of less than 8 km/h (5 MPH). The distance and location of the object is determined by 4 object sensors located in the rear bumper. The parking assist system will notify the driver using audible beeps through the radio or haptic pulses through the driver's seat. The driver can select between audible or haptic alerts in the vehicle personalization menus. See the user's manual for more detailed information on vehicle personalization.

The parking assist system is made up of the following components

1. Parking assist control module
2. Rear object sensors
3. Parking assist switch
4. Parking assist indicator
5. Radio
6. Safety Alert Seat, if equipped.

Parking Assist Control Module

The parking assist control module provides a reference voltage and a low reference to the 4 object alarm sensors. The parking assist control module receives individual signals from each of the 4 sensors and determines the location and distance of an object based on these inputs. When an object is detected, the parking assist control module will send a data message via serial data to the radio requesting an audible alert.

Object Sensors

The object sensors are located in the rear bumpers of the vehicle. The sensors are used to determine the distance between an object and the bumper. Each sensor emits an ultrasonic frequency which is reflected off any object located in front of or behind the vehicle. These reflections are received by the sensors. The time difference between the emission of the frequency and when the reflection is received is known as sensor echo time, it is used to determine the distance to the object. The sensors report this information to the parking assist control module.

Parking Assist Switch

The parking assist can be activated and deactivated by pressing the parking assist switch. By engaging the reverse gear the parking assist can also be activated. By subsequently pressing the parking assist switch the parking assist can be disabled again.

Parking Assist Indicator

The indicator in the parking assist switch shows the status of the parking assist. If the lamp is ON, the parking assist is activated.

Radio

The radio controls the audible alert for the park assist alert. If the an object is detected the radio will command beeps as an audible alert to the driver.

Safety Alert Seat

The memory seat module controls the haptic alert provided by the seats. If an object is detected, the memory seat module will command pulses to the driver's seat.

When an object is within the measuring range of the sensor, the ultrasonic pulse is reflected and is received by the sending or a neighboring sensor. The sensor converts this signal into a voltage signal and sends this signal to the parking assist control module. The parking assist control module evaluates the received sensor signals. As soon as an object is within the measuring range, the parking assist control module sends a message via serial data to the radio or seat module to provide an alert signal.

The parking assist system can detect objects greater than 7.6 cm (3 in) wide and 25.4 cm (10 in) tall. The system cannot detect objects below the bumper, underneath the vehicle.

The parking assist can be activated and deactivated by pressing the parking assist switch. When REVERSE gear is selected, park assist is automatically activated. By subsequently pressing the parking assist switch the parking assist can be disabled again.

The parking assist control module carries out a self test and monitors the sensors for electrical and mechanical faults. Monitored is the power supply of each sensor and the sensor signals, which need to alter when the vehicle moves. If this is not the case, the sensor is acoustically blocked or faulty. Mud, ice and snow may cause obstruction of the function of the sensors. The parking assist control module also checks whether the correct type of sensor is installed. If any of these tests fails, a DTC with corresponding symptom is set, the parking assist is deactivated and the parking assist indicator in the instrument panel cluster is activated.

Side Blind Zone Alert Operation

When the vehicle is started, both outside mirror displays will briefly come on to indicate that the system is operating. The system is designed to detect objects of interest as small as a 125cc motorcycle with rider. The detection zone starts at the outside rearview mirror and extends out to 3.5 m (11 ft) at the back corner of the vehicle and 3 m (10 ft) behind the vehicle at a height of 0.5 m (1.5 ft) to 2.0 m (6 ft) above the ground. The side blind zone system does not detect stationary objects such as guardrails, posts, curbs, walls, berms, bridges, or parked vehicles.

When the system detects a vehicle in the side blind zone while driving forward, independent if passing a vehicle or being passed, an amber warning symbol will light up in the appropriate outside mirror. This indicates that it may be unsafe to change lanes. If the driver then activates the turn signal, the amber warning symbol starts flashing as an extra warning not to change lanes.

Foul weather may affect the operation of the side blind zone system. Occasional missed alerts can occur under normal circumstances and will increase in wet conditions. The number of missed alerts will increase with increased rainfall or road spray. Heavy rainfall, as well as mud, dirt, snow, ice, or slush build-up on the rear fascia, can completely disable the system.

If the vehicle is towing a trailer or has an object such as a bicycle rack attached to the rear of the vehicle, the side blind zone system may not function properly and the indicators may illuminate intermittently or remain illuminated all the time.

Rear Cross Traffic Alert Operation

The rear cross traffic alert system is designed to detect objects of interest as small as a 125cc motorcycle with rider. The detection zone extends approximately 30m (99 ft) from the rear corner of the car and covers an area from behind the vehicle to 125 degrees towards the front at a height of 0.45m (1.5 ft) to 2M (6.5 ft) above ground. The system operates when vehicle speed is 10 kph (6 mph) or less and is designed to detect objects moving at speeds up to 36 kph (22 mph).

When the vehicle is backing up, the side object sensors receive energy that is reflected from external objects and determine if the objects are objects of interest or not. The system may at times detect pedestrians, shopping carts, or similar moving objects. This is normal and should not be considered as a false alert or problem with the system. The rear cross traffic alert system will estimate vehicle travel trajectory and use the information in conjunction with object travel trajectory information to determine if there is a potential collision between the vehicle and the object of interest. The rear cross traffic alert function will only alert on objects of interest that pose a potential collision with the host vehicle. The system is not designed to provide an alert to objects that have no potential collision with vehicle. In addition, the system will not alert to stationary objects such as signs, parked cars, etc.

Lane Departure Warning Operation

System operation can be described by the following modes

1. Off State: The system has been turned off by the driver using the lane departure warning switch. The lane departure warning indicator will not be illuminated.
2. Not Ready To Assist: The system is enabled and the lane departure warning indicator is illuminated, but not ready to assist when any of the following conditions is true: Vehicle speed is less than 56 km/h (35 MPH). The system is designed to function at speeds greater than 56 km/h (35 MPH). The system cannot detect lane markings. This may be because there are no lane markings, as on a country road or that the lane markings cannot be determined due to snow, rain, or other driving conditions. The windshield area in front of the camera or the camera lens is blocked by fog, dirt, damage to the windshield or other elements that may prevent the camera from detecting lane markings.
3. Ready To Assist: The system is enabled and ready to warn of the unintentional lane crossing. The system is ready to assist when the green lane departure warning indicator is illuminated on the vehicle direction display.

Lane Crossing Alerts

1. When one of the following conditions are met, the system will not give alerts: The correct turn signal is activated. An activated turn signal is interpreted as an intentional lane crossing. The operator makes an intentional steering maneuver. The operator makes an intentional accelerating maneuver. The operator makes an intentional braking maneuver.
2. Lane crossing alert consists of the following: The amber lane departure warning indicator will flash. Three chimes are activated through the radio. or if equipped, three pulses to the left or right side of the seat.

Object Detection Description and Operation (with Haptic Signal Motor Seat)

The Active Safety Seats provide a vibration in the driver's seat bottom cushion to alert the driver of a number of concerns. There are two motors providing the vibration and are located on the left and right sides. Depending on the alert, either the left, right or both motors will activate.

The Active Safety Seat is made up of the following components

1. Seat Memory Control Module
2. Haptic Signal Motor - Driver Left Rear
3. Haptic Signal Motor - Driver Right Rear

Seat Memory Control Module

The Seat Memory Control Module receives serial data messages from other modules and provides a voltage output to turn on the haptic signal motors. The Seat Memory Control Module will pulse the left, right, or both motors the number of pulses requested over serial data. The module monitors the circuits for open, short to ground, and short to voltage conditions and will set DTCs if a problem is detected. The modules that can request haptic motor operation are

1. Front and Rear Parking Assist Control Module (Front and Rear Parking Assist)
2. Vehicle Camera Module (Lane Departure Warning, Forward Collision Alert)
3. Side Object Sensor Modules (Rear Cross Traffic Alert)

Haptic Signal Motors - Driver Left Rear and Driver Right Rear

The motors are located in the driver's seat bottom cushion and are positioned on the left and right sides. The motors are connected to ground and receive voltage from the Seat Memory Control Module. There are no connectors other than at the Seat Memory Control Module.

Active Safety Seat Operation

System operation can be described by the following alerts

1. Front and Rear Parking Assist - when an object is first detected both motors will be pulsed twice. If a potential crash is detected, both motors will be pulsed five times.
2. Lane Departure Warning - when the vehicle crosses a lane marking either the left or right motor will be pulsed three times depending on which side the warning is for.
3. Forward Collision Alert warning - both motors will be pulsed five times.
4. Rear Cross Traffic Alert - When backing up, if rear cross traffic is detected, either the left or right motor will be pulsed three times, depending on which side the warning is for.

Adaptive Cruise Control Description

The adaptive cruise control functionality depends on various modules on the vehicle to function and each module performs a function that is critical to the proper operation of the adaptive cruise control system. Adaptive cruise control will not operate if any components fail. Communication between modules is via serial data. The following is a functional description of the active safety control module and the other associated components

Active Safety Control Module

The Active Safety Control Module analyzes data from various modules, sensors, and switches to provide enhanced safety features. Refer to Object Detection Description and Operation (with Active Safety System, UGN, N America) , Object Detection Description and Operation (with Front and Rear Park Assist, UD5) , Object Detection Description and Operation (with Rear Park Assist, UD7) , Object Detection Description and Operation (with Side Blind Zone Alert, UFT, N America) , Object Detection Description and Operation (with Rear Cross Traffic Alert, UFG, N America) , Object Detection Description and Operation (with Forward Collision Alert, UEU) , Object Detection Description and Operation (with Lane Departure Warning, UFL) , Object Detection Description and Operation (with Haptic Signal Motor Seat) , Object Detection Description and Operation (with Adaptive Cruise Control, KSG, N America) , Object Detection Description and Operation (with Active Safety System, UGN, except N America) , Object Detection Description and Operation (with Adaptive Cruise Control, KSG, except N America) , Object Detection Description and Operation (with Side Blind Zone Alert, UFT, Except N America) , Object Detection Description and Operation (with Rear Cross Traffic Alert, UFT, Except N America) for more information. In addition to enhanced safety features, the active safety control module provides the adaptive cruise control system functionality. The active safety control module analyzes data from the long range radar sensor module, front short range radar sensor modules, and frontview camera module to identify and classify objects in the road environment. The system scans the road environment to detect targets within its specified field of view. The active safety control module then sends throttle and/or brake commands to the engine control module (ECM) and electronic brake control module (EBCM) via serial data in order to control the vehicle acceleration/deceleration based on the data from the modules. The ECM and EBCM provide throttle control and automatic braking needed for proper cruise speed adjustment. The following is a list of the active safety control module functions pertaining to the adaptive cruise control functionality

1. The active safety control module processes the road environment to get data concerning any vehicle ahead of the adaptive cruise control vehicle. Detection, parameter estimation, tracking, object classification and diagnostics are the primary functions. When an object is detected, the controller calculates the object range, range rate, acceleration and azimuth angle parameters.
2. The active safety control module performs adaptive cruise control state processing automatically - distance control or speed control. The adaptive cruise control operates in 2 possible states - cruise or follow. The normal operating state is cruise, whereby the vehicle speed is controlled to match the driver selected set speed. When a preceding forward target is identified, the adaptive cruise control system will automatically transition into the follow speed state to provide proper lane spacing behind the target vehicle in front. The preceding vehicle's speed and acceleration, with the adaptive cruise control vehicle speed, acceleration and distance between the two vehicles will be used to determine the adaptive cruise control follow speed limit. The adaptive cruise control follow speed limit will ensure that an acceptable distance is maintained to the preceding vehicle.
3. The active safety control module determines the follow speed limit for throttle control by the ECM.
4. The active safety control module arbitrates the adaptive cruise control system brake and throttle control between the EBCM and the ECM.
5. The active safety control module requests brake light activation during automatic braking.
6. The active safety control module provides operational feedback to the vehicle driver. The active safety control module sends signals for telltales and messages to be displayed on the instrument cluster or driver information center.

Body Control Module (BCM)

The following are the adaptive cruise control System functions provided by the BCM

1. The BCM provides a translating gateway for the high speed GMLAN serial data circuit.
2. The BCM reads all cruise control switches and the gap switch. The active safety control module monitors a variety of user operated switches from the BCM switch status information sent via the GMLAN serial data circuit.
3. The BCM illuminates the brake light based on a GMLAN message from the active safety control module during automatic braking.
4. The BCM measures the brake pedal position and sends brake pedal travel status via GMLAN serial data circuit to the ECM. The ECM disengages the adaptive cruise control system when the brake is applied by the driver pressing the brake pedal.
5. The BCM serves as a gateway to the instrument cluster and driver information center. The BCM will generate visual warnings based on high speed GMLAN serial data messages from the active safety control module.

Engine Control Module (ECM)

The following are the adaptive cruise control system functions performed by the ECM

1. The ECM provides the electronic throttle control to the adaptive cruise control System. The ECM is also responsible for determining when a driver is overriding the adaptive cruise control throttle position by pressing the accelerator pedal.
2. The ECM processes the cruise control switch requests received via the GMLAN serial data circuit from the BCM. Engaging and disengaging the adaptive cruise control system are functions performed by the ECM.
3. The ECM determines the driver selected vehicle speed. Unless the adaptive cruise control module requests a lower vehicle speed, the ECM will control the vehicle speed to the driver selected set speed.
4. The ECM allows automatic braking without disengaging the adaptive cruise control.

Antilock Brake System (ABS)

The following are the adaptive cruise control System functions performed by the EBCM

1. The EBCM controls the operation of the Antilock Brake System.
2. The EBCM provides automatic braking for the adaptive cruise control system. The active safety control module will request vehicle deceleration via high speed GMLAN serial data circuit.
3. The EBCM determines when the driver-applied brake pressure is active. The EBCM will communicate this status via the GMLAN serial data circuit to the BCM.
4. The EBCM releases vehicle automatic braking when there is a throttle override by the driver pressing the accelerator.
5. The EBCM predicts brake temperatures. Due to automatic braking, the brake system may overheat. When the brakes are overheated, the EBCM requests the adaptive cruise control System to be temporarily shut down by the ECM until the brakes cool to a normal operating temperature.

Refer to ABS Description and Operation .

Transmission Control Module (TCM)

The transmission control module (TCM) provides a down shift to protect the brakes. When the TCM detects some driver braking activity or adaptive cruise control automatic braking activity, the TCM down shifts the vehicle transmission to increase engine braking. This helps reduce braking activity, extend brake pad life and reduce brake system overheating.

Driver Information Center

The driver information center is a part of the instrument cluster and displays the adaptive cruise control system warning messages. The active safety control module requests messages to be displayed on the driver information center by sending a GMLAN request to the BCM. The BCM sends a GMLAN serial data request to the instrument cluster demanding the display of the warning message. When the message is acknowledged by the driver and the cause of the message resolved, the driver information center turns the message off. The adaptive cruise control system will not operate if the driver information center fails.

Brake Pedal Position Sensor

The BCM monitors the brake pedal position sensor in order to determine when pressure is being applied to the brake by the driver stepping on the brake pedal. The brake pedal position sensor receives a low reference signal and a 5 V reference from the BCM. When the brake is applied, a signal is applied from the brake pedal position sensor through the brake pedal position sensor signal circuit to the BCM. The BCM utilizes this signal in deciding when to command the activation of the stop lamps. The BCM continuously sends signals via the GMLAN serial data circuit to the EBCM and the ECM reflecting the brake pedal position status. This will include the initial brake travel signal required for the activation of the adaptive cruise control system. The adaptive cruise control system will not engage unless the initial brake pedal travel signal is valid and received by the BCM. When the BCM brake pedal position signal indicates that brake pedal pressure is being applied by the driver when the adaptive cruise control System is engaged, the ECM immediately disengages the adaptive cruise control System. Re-engaging the adaptive cruise control System will require the driver pressing the set or resume switch. Refer to Brake Pedal Position Sensor Calibration , and to Exterior Lighting Systems Description and Operation for more information on the brake pedal pressure sensor.

Accelerator Pedal

Deceleration of the adaptive cruise control vehicle to maintain a certain distance and speed while a slower moving vehicle is in its path is achieved through throttle control by the ECM and the application of automatic braking by the EBCM. During automatic braking the ECM is commanded to release the throttle from the currently controlled cruise position by the active safety control module. At the end of automatic braking, the ECM will control the vehicle speed to the current set vehicle speed. Driver throttle override occurs when the driver of the adaptive cruise control vehicle depresses the accelerator pedal with the intention of requesting greater speed than the current throttle position. An example is an adaptive cruise control vehicle driver stepping on the accelerator for a passing maneuver. The ECM continuously monitors the throttle and reports a throttle override condition. When no throttle override is present, automatic braking is allowed. When throttle override is detected by the ECM, automatic braking in not allowed to affect the vehicle acceleration.

Object Detection Description and Operation (with Active Safety System, UGN, except N America)

The Active Safety System

The Active Safety System analyzes data from various sensors and modules to provide multiple features. It is made up of the following components

1. Active Safety Control Module
2. Park Assist Switch and Indicator
3. Lane Departure Warning Switch and Indicator
4. Frontview Camera Module
5. Radar Sensor Module - Long Range

Active Safety Control Module

The Active Safety Control Module analyzes data from various modules, sensors, and switches to provide enhanced safety features. Inputs and outputs can either be connected directly to the Active Safety Control Module or communicate though serial data. The Active Safety Control Module communicates on a dedicated Object Bus to the long range radar sensor module and the Frontview Camera Module. A problem on the Object Bus may result in multiple DTCs since the Active Safety Control Module may not be able to communicate with some or all modules on the bus. See Data Link Communications Description and Operation for more serial data information.

The Active Safety Control Module will alert the driver to a vehicle ahead and provide forward collision alert and lane departure warnings. The alerts and warnings can be user-selected to be audible through the audio system or haptic using the Active Safety Seat. In addition, the Active Safety Control Module will provide driver assistance through integrated brake assist, automatic collision preparation, and adaptive cruise control.

If there is a DTC set in any of the modules that the Active Safety Control Module uses as inputs, it will send a "Service Driver Assist" to the instrument cluster to alert the driver of a problem with the system. No other specific details are given unless the driver attempts to activate a specific system. For example if the driver attempts to turn on Lane Departure Warning, the instrument cluster will display "Lane Departure Unavailable" and the indictor will flash and then go out. A scan tool must be used to read the DTCs that are causing the malfunction to help find the problem.

1. Active Safety Control Module Inputs: Park Assist Switch Lane Departure Warning Switch Forward Collision Alert Switch Radar Sensor Module - Long Range Frontview Camera Module Front and Rear Park Assist Module Multi-axis Acceleration Sensor Wheel Speed Sensors Steering Wheel Angle Sensor EBCM
2. Active Safety Control Module Outputs: ECM TCM EBCM ONSTAR BCM Memory Seat Module (for haptic seat alerts) Instrument Cluster (for alerts and heads up display if equipped) Radio (for audio alerts) Park Assist Switch Indicator Lane Departure Warning Switch Indicator

Parking Assist Switch

Parking assist can be activated or deactivated by pressing the parking assist switch. See owners manual for exact location of the park assist switch. The Parking Assist Switch is hard-wired to the Active Safety Control Module. The switch contains a LED that is controlled by the Active Safety Control Module to indicate if the parking assist feature is enabled.

Lane Departure Warning Switch

The Lane Departure Warning feature can be activated or deactivated by pressing the Lane Departure Warning Switch. See owners manual for exact location of the Lane Departure Warning Switch. The Lane Departure Warning Switch is hard-wired to the Active Safety Control Module. The switch contains a LED that is controlled by the Active Safety Control Module to indicate if lane departure warning feature is enabled.

Forward Collision Alert Switch

The Forward Collision Alert System can be adjusted to set the range of the warning by pressing the Forward Collision Alert Switch. The Forward Collision Alert can be set to Far, Medium, Near, or Off. See owners manual for exact location of the Forward Collision Alert Switch. The Forward Collision Alert Switch is hard-wired to the Body Control Module and is communicated to the Active Safety Control Module through serial data.

Radar Sensor Module - Long Range

The Radar Sensor Module - Long Range is located behind the front grille emblem and is used in the 30-200 meters (98-656 ft) range. The Radar Sensor Module - Long Range communicates on the Object Bus to the Active Safety Control Module. In addition to the wiring harness ground, the module is grounded through the mounting bracket.

Frontview Camera Module

The Frontview Camera Module is located behind the windshield, looking out at the road ahead and detects lane markings and vehicles directly ahead, within a distance of approximately 60 meters (197 ft). The Frontview Camera Module is used for lane departure warning and forward collision alert systems. The Frontview Camera Module communicates on the Object Bus to the Active Safety Control Module.

Front and Rear Park Assist Module

The Front and Rear Park Assist Module uses ultrasonic object sensors located in the front and rear bumper fascia to provide distance measurements to nearby objects. The Front and Rear Park Assist Module sends rear object data to the Active Safety Control Module on the Low Speed GMLAN.

The adaptive cruise control functionality depends on various modules on the vehicle to function and each module performs a function that is critical to the proper operation of the adaptive cruise control system. Adaptive cruise control will not operate if any components fail. Communication between modules is via serial data. The following is a functional description of the active safety control module and the other associated components

Active Safety Control Module

The Active Safety Control Module analyzes data from various modules, sensors, and switches to provide enhanced safety features. Refer to Object Detection Description and Operation (with Active Safety System, UGN, N America) , Object Detection Description and Operation (with Front and Rear Park Assist, UD5) , Object Detection Description and Operation (with Rear Park Assist, UD7) , Object Detection Description and Operation (with Side Blind Zone Alert, UFT, N America) , Object Detection Description and Operation (with Rear Cross Traffic Alert, UFG, N America) , Object Detection Description and Operation (with Forward Collision Alert, UEU) , Object Detection Description and Operation (with Lane Departure Warning, UFL) , Object Detection Description and Operation (with Haptic Signal Motor Seat) , Object Detection Description and Operation (with Adaptive Cruise Control, KSG, N America) , Object Detection Description and Operation (with Active Safety System, UGN, except N America) , Object Detection Description and Operation (with Adaptive Cruise Control, KSG, except N America) , Object Detection Description and Operation (with Side Blind Zone Alert, UFT, Except N America) , Object Detection Description and Operation (with Rear Cross Traffic Alert, UFT, Except N America) for more information. In addition to enhanced safety features, the active safety control module provides the adaptive cruise control system functionality. The active safety control module analyzes data from the long range radar sensor module and frontview camera module to identify and classify objects in the road environment. The system scans the road environment to detect targets within its specified field of view. The active safety control module then sends throttle and/or brake commands to the engine control module (ECM) and electronic brake control module (EBCM) via serial data in order to control the vehicle acceleration/deceleration based on the data from the modules. The ECM and EBCM provide throttle control and automatic braking needed for proper cruise speed adjustment. The following is a list of the active safety control module functions pertaining to the adaptive cruise control functionality

1. The active safety control module processes the road environment to get data concerning any vehicle ahead of the adaptive cruise control vehicle. Detection, parameter estimation, tracking, object classification and diagnostics are the primary functions. When an object is detected, the controller calculates the object range, range rate, acceleration and azimuth angle parameters.
2. The active safety control module performs adaptive cruise control state processing automatically - distance control or speed control. The adaptive cruise control operates in 2 possible states - cruise or follow. The normal operating state is cruise, whereby the vehicle speed is controlled to match the driver selected set speed. When a preceding forward target is identified, the adaptive cruise control system will automatically transition into the follow speed state to provide proper lane spacing behind the target vehicle in front. The preceding vehicle's speed and acceleration, with the adaptive cruise control vehicle speed, acceleration and distance between the two vehicles will be used to determine the adaptive cruise control follow speed limit. The adaptive cruise control follow speed limit will ensure that an acceptable distance is maintained to the preceding vehicle.
3. The active safety control module determines the follow speed limit for throttle control by the ECM.
4. The active safety control module arbitrates the adaptive cruise control system brake and throttle control between the EBCM and the ECM.
5. The active safety control module requests brake light activation during automatic braking.
6. The active safety control module provides operational feedback to the vehicle driver. The active safety control module sends signals for telltales and messages to be displayed on the instrument cluster or driver information center.

Body Control Module (BCM)

The following are the adaptive cruise control System functions provided by the BCM

1. The BCM provides a translating gateway for the high speed GMLAN serial data circuit.
2. The BCM reads all cruise control switches and the gap switch. The active safety control module monitors a variety of user operated switches from the BCM switch status information sent via the GMLAN serial data circuit.
3. The BCM illuminates the brake light based on a GMLAN message from the active safety control module during automatic braking.
4. The BCM measures the brake pedal position and sends brake pedal travel status via GMLAN serial data circuit to the ECM. The ECM disengages the adaptive cruise control system when the brake is applied by the driver pressing the brake pedal.
5. The BCM serves as a gateway to the instrument cluster and driver information center. The BCM will generate visual warnings based on high speed GMLAN serial data messages from the active safety control module.

Engine Control Module (ECM)

The following are the adaptive cruise control system functions performed by the ECM

1. The ECM provides the electronic throttle control to the adaptive cruise control System. The ECM is also responsible for determining when a driver is overriding the adaptive cruise control throttle position by pressing the accelerator pedal.
2. The ECM processes the cruise control switch requests received via the GMLAN serial data circuit from the BCM. Engaging and disengaging the adaptive cruise control system are functions performed by the ECM.
3. The ECM determines the driver selected vehicle speed. Unless the adaptive cruise control module requests a lower vehicle speed, the ECM will control the vehicle speed to the driver selected set speed.
4. The ECM allows automatic braking without disengaging the adaptive cruise control.

Antilock Brake System (ABS)

The following are the adaptive cruise control System functions performed by the EBCM

1. The EBCM controls the operation of the Antilock Brake System.
2. The EBCM provides automatic braking for the adaptive cruise control system. The active safety control module will request vehicle deceleration via high speed GMLAN serial data circuit.
3. The EBCM determines when the driver-applied brake pressure is active. The EBCM will communicate this status via the GMLAN serial data circuit to the BCM.
4. The EBCM releases vehicle automatic braking when there is a throttle override by the driver pressing the accelerator.
5. The EBCM predicts brake temperatures. Due to automatic braking, the brake system may overheat. When the brakes are overheated, the EBCM requests the adaptive cruise control System to be temporarily shut down by the ECM until the brakes cool to a normal operating temperature.

Refer to ABS Description and Operation .

Transmission Control Module (TCM)

The transmission control module (TCM) provides a down shift to protect the brakes. When the TCM detects some driver braking activity or adaptive cruise control automatic braking activity, the TCM down shifts the vehicle transmission to increase engine braking. This helps reduce braking activity, extend brake pad life and reduce brake system overheating.

Driver Information Center

The driver information center is a part of the instrument cluster and displays the adaptive cruise control system warning messages. The active safety control module requests messages to be displayed on the driver information center by sending a GMLAN request to the BCM. The BCM sends a GMLAN serial data request to the instrument cluster demanding the display of the warning message. When the message is acknowledged by the driver and the cause of the message resolved, the driver information center turns the message off. The adaptive cruise control system will not operate if the driver information center fails.

Brake Pedal Position Sensor

The BCM monitors the brake pedal position sensor in order to determine when pressure is being applied to the brake by the driver stepping on the brake pedal. The brake pedal position sensor receives a low reference signal and a 5 V reference from the BCM. When the brake is applied, a signal is applied from the brake pedal position sensor through the brake pedal position sensor signal circuit to the BCM. The BCM utilizes this signal in deciding when to command the activation of the stop lamps. The BCM continuously sends signals via the GMLAN serial data circuit to the EBCM and the ECM reflecting the brake pedal position status. This will include the initial brake travel signal required for the activation of the adaptive cruise control system. The adaptive cruise control system will not engage unless the initial brake pedal travel signal is valid and received by the BCM. When the BCM brake pedal position signal indicates that brake pedal pressure is being applied by the driver when the adaptive cruise control System is engaged, the ECM immediately disengages the adaptive cruise control System. Re-engaging the adaptive cruise control System will require the driver pressing the set or resume switch. Refer to Brake Pedal Position Sensor Calibration , and to Exterior Lighting Systems Description and Operation for more information on the brake pedal pressure sensor.

Accelerator Pedal

Deceleration of the adaptive cruise control vehicle to maintain a certain distance and speed while a slower moving vehicle is in its path is achieved through throttle control by the ECM and the application of automatic braking by the EBCM. During automatic braking the ECM is commanded to release the throttle from the currently controlled cruise position by the active safety control module. At the end of automatic braking, the ECM will control the vehicle speed to the current set vehicle speed. Driver throttle override occurs when the driver of the adaptive cruise control vehicle depresses the accelerator pedal with the intention of requesting greater speed than the current throttle position. An example is an adaptive cruise control vehicle driver stepping on the accelerator for a passing maneuver. The ECM continuously monitors the throttle and reports a throttle override condition. When no throttle override is present, automatic braking is allowed. When throttle override is detected by the ECM, automatic braking in not allowed to affect the vehicle acceleration.

The side blind zone alert system shall detect and report "objects of interest" on either side of the vehicle, within a specified "blind spot" zone. The system is designed to alert the driver, with a visual display placed on the side view mirror, to the presence of objects of interest that may not be visible in the inside rearview mirror and outside rear view mirrors. Although this system is intended to help drivers avoid lane change crashes, it does not replace driver vision and therefore should be considered a lane change aid. Even with the side blind zone alert system, the driver must check carefully for objects outside of the reporting zone before changing lanes. In the event that the system senses a malfunction through its diagnostic routines, the system will be disabled and the driver will be visually notified.

When the vehicle is started, both outside mirror displays will briefly come on to indicate that the system is operating. The warning symbols will vary brightness based on the ambient light conditions. Side blind zone alert is active when the vehicle is out of park or the parking brake is off on manual transmission vehicles. When the system detects a vehicle in the side blind zone while driving forward, an amber warning symbol will light up in the appropriate outside mirror. This indicates that it may be unsafe to change lanes. If the driver then activates the turn signal, the amber warning symbol starts flashing as an extra warning not to change lanes.

The system is designed to detect objects of interest as small as a 125cc motorcycle with rider. The detection zone starts at the outside rearview mirror and extends out to 3.5 m (11 ft) at the back corner of the vehicle and 5m (16 ft) behind the vehicle at a height of 0.5 m (1.5 ft) to 2.0 m (6 ft) above the ground. The side blind zone system does not detect stationary objects such as guardrails, posts, curbs, walls, berms, bridges, or parked vehicles.

If the vehicle is towing a trailer or has an object such as a bicycle rack attached to the rear of the vehicle, the side blind zone system may not function properly and the indicators may illuminate intermittently or remain illuminated all the time. The driver information center may display "SIDE DETECTION SYSTEM UNAVAILABLE".

Foul weather may affect the operation of the side blind zone system. Occasional missed alerts can occur under normal circumstances and will increase in wet conditions. The number of missed alerts will increase with increased rainfall or road spray. Heavy rainfall, as well as mud, dirt, snow, ice, or slush build-up on the rear fascia, can completely disable the system. The warning symbols will vary brightness based on the ambient light conditions.

The rear cross traffic alert system is designed to detect moving objects of interest as small as a 125cc motorcycle with rider. The detection zone extends approximately 30m (99 ft) from the rear corner of the car and covers an area from behind the vehicle to 125 degrees towards the front at a height of 0.45m (1.5 ft) to 2m (6.5 ft) above ground. The system operates when vehicle speed is 10 kph (6 mph) or less and is designed to detect objects moving at speeds up to 36 kph (22 mph).

When the vehicle is backing up, the side object sensors receive energy that is reflected from external objects and determine if the objects are objects of interest or not. The system may at times detect pedestrians, shopping carts, or similar moving objects. This is normal and should not be considered as a false alert or problem with the system. The rear cross traffic alert system will estimate vehicle travel trajectory and use the information in conjunction with object travel trajectory information to determine if there is a potential collision between the vehicle and the object of interest. The rear cross traffic alert function will only alert on objects of interest that pose a potential collision with the host vehicle. The system is not designed to provide an alert to objects that have no potential collision with vehicle. In addition, the system will not alert to stationary objects such as signs, parked cars, etc.

If the vehicle is towing a trailer or has an object such as a bicycle rack attached to the rear of the vehicle, the rear cross traffic alert system may not function properly.

Foul weather may affect the operation of the rear cross traffic alert system. Occasional missed alerts can occur under normal circumstances and will increase in wet conditions. The number of missed alerts will increase with increased rainfall or road spray. Heavy rainfall, as well as mud, dirt, snow, ice, or slush build-up on the rear fascia, can completely disable the system.