Contents Wiring diagrams Section: Collision/avoidance All sections

Object Detection System: Overview Chevrolet Malibu VIII facelift

Collision/avoidance 4 illustrations ~3295 words

Scheme 1

Scheme 1: Rear Park Assist (UD7)

Scheme 2

Scheme 2: Lane Departure Warning (UFL) and Forward Collision Alert (UEU)

Scheme 3

Scheme 3: Rear Cross Traffic Alert (UFG) and Side Object Detection (UFT)

Scheme 4

Scheme 4: Rearview Camera (UVC)

Circuit/System Description

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 8 V reference circuit and provides ground via the 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 signal circuit to calculate the distance and position of an object.

The parking assist can be activated/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.

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

The lane departure warning is enabled and disabled through a switch located in the instrument panel. When the switch is pressed once, the frontview camera module disable or enable the lane departure warning. When the lane departure warning system is enabled the frontview camera module will illuminate the indicator in the switch.

The frontview camera module permanently monitors the serial data bus for error messages. When a malfunction is detected by the frontview camera module, the system will be disabled and an error message will be stored in the frontview 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 and the frontview camera module receive the vehicle identification number (VIN) from the body control module. The control module will compare the VIN received to the VIN stored in memory.

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 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 may also sound three times when the yellow instrument cluster indicator is flashing.

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 ultrasonic parking assist system is designed to identify and notify the driver of an object in the vehicle's path when moving in reverse at speeds of less than 8 km/h (5 MPH). The distance and location of the object is determined by four object sensors, located in the rear fascia. The parking assist system will notify the driver using an audible signal through the radio.

When the transmission is placed into REVERSE, a 12 V signal is sent to the 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 radio 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 lane departure warning is controlled by the frontview camera module mounted on the windshield. The lane departure warning is enabled and disabled through a switch located at the instrument panel. When enabled, the vehicle direction camera control module will illuminate the indicator located in the switch.

When the system is operating and can detect the lane markings, the vehicle direction camera control module will request via serial data communications that the instrument 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.

Object Detection Description and Operation (Lane Departure Warning, UFL)

The lane departure warning system is a convenience feature of the front view camera that issues a warning when the system detects that the vehicle has unintentionally crossed a lane marking. The front view camera is located behind the windshield, looking out at the road ahead and detecting any lane markings. When the vehicle unintentionally leaves a detected lane, a visual and audible alert is given to the driver.

The lane departure warning system is made up of the following components

  1. Front view camera module
  2. Lane departure warning switch
  3. Instrument cluster / Vehicle Direction Display
  4. Radio

Front View Camera Module

The camera detects visual queues such as lane markings. When it is determined that the vehicle has unintentionally moved outside of the lane, a visual and audible warning is given to the driver. The front view camera module receives an input from the lane departure warning switch and controls the lane departure warning switch indicator output. The front view camera module also communicates via serial data with the instrument cluster and radio to request visual and audible alerts.

Lane Departure Warning Switch

The lane departure warning switch provides an input to the front view camera module to turn the lane departure warning system ON and OFF. The front view camera module provides a signal voltage to the normally open momentary switch. When the switch is pressed, the signal circuit is pulled to ground, indicating to the front view camera module that the system has been requested to turn ON or OFF. The lane departure warning switch also contains the lane departure warning switch indicator, which is controlled by the front view camera module to indicate the ON and OFF status of the lane departure warning system. When the system has been enabled by the lane departure warning switch, the front view camera module applies ground to the switch indicator and illuminates the LED. The location of the lane departure warning switch can vary with different vehicles. For the exact location please refer to the user's manual.

Instrument Cluster

The vehicle direction display contains green and amber lane departure warning indicators. These indicate to the driver the current status of the lane departure warning system and are controlled via serial data by the front view camera module. When the vehicle speed is above 56 km/h (35 MPH) and the system has detected the required lane markings and is ready to assist, the green indicator will be illuminated on the vehicle direction display. If the vehicle has unintentionally left the lane, the amber indicator will flash.

Radio

The radio controls the audible alert for the lane departure warning. If the vehicle has unintentionally left the lane, the radio will command three beeps as an audible alert to the driver.

Lane Departure Warning Operation

System operation can be describe 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: Three chimes are activated through the radio. The amber lane departure warning indicator will flash.

Rear Vision Camera System Operation

The rear vision camera system consists of a video camera located at the rear of the vehicle and the navigation radio.

When the transmission is placed into REVERSE, a 12 volt signal is sent to the rear vision camera by the body control module (BCM). This signal indicates to the camera that the vehicle is in reverse and image display is requested. The rear vision camera receives ignition voltage and a constant ground to power the camera. Video signal + and video signal - circuits carry the video image from the rear vision camera to the navigation radio. Additionally, the video signal circuits are shielded to prevent any interference which may lead to a loss of video signal resolution and a degraded video image. The shield is provided a ground path by the rear vision camera.

The following conditions may cause a degraded rear vision camera image

  1. Ice, snow, or mud has built up on the rear vision camera
  2. Dark conditions
  3. Extreme light conditions, such as glare from the sun or the headlights of another vehicle
  4. Damage to the rear of the vehicle
  5. Extreme high temperatures or extreme temperature changes

If a malfunction is detected in the system, Service Rear Vision Camera may be displayed on the navigation radio as an indicator to the customer that a problem exists that requires service.

Object Detection Description and Operation (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.

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 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.

Object Detection Description and Operation (Foward Collision Alert, UEU)

The forward collision alert system is a convenience feature of the front view camera that issues a warning to the driver when a potential collision risk exists. The front view camera is located behind the windshield, looking out at the road ahead and detecting vehicles directly ahead, within a distance of approximately 60 meters (197 ft). The forward collision alert system is always active and operates at speeds above 40 kph (25 mph). When the system detects a vehicle in the path ahead, the green vehicle ahead indicator in the vehicle direction display is illuminated. When approaching another vehicle too rapidly, the collision alert symbol will flash in the vehicle direction display. Simultaneously an audible alert sounds. Forward collision alert does not warn the driver of any objects that are not detected as a vehicle, like e.g. pedestrians, animals, signs, guard rails, bridges, construction barrels or other stationary or slow moving objects. The forward collision alert timing sensitivity to control the distance to the vehicle ahead can be set using the forward collision alert switch in the left steering wheel controls.

In some cases the camera may detect a vehicle that is not in the path ahead, or the system may occasionally provide unrealistic alerts. This could respond to a turning vehicle ahead, guard rails, traffic signs, or other stationary objects. This is normal operation, the vehicle does not need service. Forward collision alert may sometimes set unnecessary alerts to turning vehicles, vehicles in other lanes, objects that are not vehicles, or shadows. These alerts are normal operation and the vehicle does not need service.

The forward collision alert system is made up of the following components

  1. Front view camera module
  2. Forward collision alert switch
  3. Instrument cluster / Vehicle direction display
  4. Radio

Front View Camera Module

The camera detects vehicles in front of the host vehicle. The front view camera module requests the green vehicle ahead alert indicator in the vehicle direction display ON via serial data when the front view camera system has detected a vehicle in the driving path ahead. The front view camera module also communicates via serial data with the driver information center and the radio to request visual and audible alerts.

  1. Lane departure warning system unavailable
  2. Forward collision alert OFF
  3. Service front camera

Forward Collision Alert Switch

The forward collision alert switch provides an input to the front view camera module to select the alert timing sensitivity when approaching another vehicle too rapidly. The front view camera module provides a signal voltage to the normally open switch. When the switch is pressed, the signal circuit is pulled to ground, indicating to the front view camera module that the system has been requested to change the alert timing sensitivity. The first button press shows the current alert timing setting on the driver information center. With every button press, the alert timing sensitivity is changed. The current alert timing setting will be maintained until it is changed. The preset alert timing setting is displayed in the top line of the driver information center. The position of the forward collision alert switch can vary with different vehicles. For the exact position please refer to the user's manual.

Instrument Cluster

The Vehicle direction display contains the green vehicle ahead indicator, which indicates to the driver that the Front View Camera system has detected a vehicle in the driving path ahead and is controlled via serial data. When approaching another vehicle too rapidly, the collision alert symbol will flash in the Vehicle direction display. The red Front collision alert display will stay continuously illuminated if the vehicle ahead remains much too close.

Radio

The radio controls the audible alert for the forward collision alert system. If the host vehicle is approaching another vehicle too rapidly, the radio will command an audible alert to the driver.