Scheme 1
Scheme 2
Circuit/System Description
The body control module (BCM) supplies B+ to the rearview camera when the transmission is placed into reverse.
The object alarm sensors are 3-wire sensors that are used to determine the distance between the vehicle and an object of interest. The object alarm module supplies 8 volts to the object alarm sensors via the 8 volt reference circuit and provides ground via the low reference circuit. The object alarm module triggers the sensors in a sequential loop. After each sensor transmits, the object alarm module uses the sensor echo received through the signal circuit to calculate the distance and position of an object.
When the ignition is turned ON, the object alarm module receives the vehicle identification number (VIN) from the body control module (BCM). The object alarm module will compare the VIN received to the VIN stored in memory.
The object alarm sensors are 3-wire sensors that are used to determine the distance between the vehicle and an object of interest. The object alarm module supplies an 8 V reference and ground reference to each of the object alarm sensors. The object alarm module triggers the sensors in a sequential loop. After each sensor transmits, the object alarm module uses the sensor echo received through the signal circuit to calculate the distance and position of an object.
The parking assist system is designed to identify and notify the driver of an object in the vehicle's path when reversing at speeds of less than 8 km/h (5 mph). The distance and location of the object is determined by four object alarm sensors located in the rear bumper. The parking assist system will notify the driver using an audible signal through the radio speakers.
When the transmission is placed into REVERSE, a 12 V signal is sent to the inside rearview mirror and rearview camera indicating that camera operation is requested. Ignition voltage and ground are supplied to the rearview camera; the inside rearview mirror is supplied a common ignition voltage and ground source that is shared with other mirror operations. The rearview camera sends video information to the inside rearview mirror 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.
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.
Rear Vision Camera System Operation (without UVB)
The components used in the rear vision camera system are the camera, located at the rear of the vehicle, and the inside rearview mirror, which houses the LCD display.
When the vehicle is placed in REVERSE, the body control module (BCM) sends a 12 volt signal to the inside rearview mirror and the rearview camera. This signal indicates that rear vision camera operation is required. Upon receipt of this signal, the mirror will begin the power up cycle for the LCD display and the camera will also power up. The rear vision camera transmits the video signal to the inside rearview mirror through discrete + and - signal circuits. A metallic foil encases the video signal circuits and is tied to a shield ground circuit. This shield is designed to reduce electronic interference which may degrade the video signal and cause a distorted or otherwise degraded image.
If desired, the rear vision camera may be manually disabled. Refer to the navigation system owners manual for instructions on manually disabling and enabling the rear vision camera system. The following conditions may cause a degraded rear vision camera image
- Ice, snow, or mud has built up on the rear vision camera
- Dark conditions
- Extreme light conditions, such as glare from the sun or the headlights of another vehicle
- Damage to the rear of the vehicle
- Extreme high or low temperatures or extreme temperature changes
Rear Vision Camera System Operation (with UVB)
The components used in the rear vision camera system are the camera, located at the rear of the vehicle, and the navigation radio.
When the vehicle is placed in REVERSE, the body control module (BCM) sends a 12 volt signal to the rearview camera. This signal indicates that rear vision camera operation is required. Upon receipt of this signal, the camera will begin the power up cycle. A serial data message is also received by the navigation radio indicating the vehicle is in REVERSE. Upon receipt of this message, the navigation radio will also begin a power up cycle for the display. The rear vision camera transmits the video signal to the navigation radio through discrete + and - signal circuits. A metallic foil encases the video signal circuits and is tied to a shield ground circuit. This shield is designed to reduce electronic interference which may degrade the video signal and cause a distorted or otherwise degraded image.
If desired, the rear vision camera may be manually disabled through the navigation system menu. Refer to the navigation system owners manual for instructions on manually disabling and enabling the rear vision camera system. The following conditions may cause a degraded rear vision camera image
- Ice, snow, or mud has built up on the rear vision camera
- Dark conditions
- Extreme light conditions, such as glare from the sun or the headlights of another vehicle
- Damage to the rear of the vehicle
- Extreme high or low 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 (UD7)
The parking assist system is designed to identify and notify the driver of an object in the vehicle's path when reversing at speeds of less than 8 km/h (5 mph). The distance and location of the object is determined by four object alarm sensors located in the rear bumper. The parking assist system will notify the driver using an audible signal through the radio speakers. The audible signal will vary depending on the distance the object is from the vehicle.
The parking assist system is made up of the following components
- Object alarm module
- Object alarm sensors
Object Alarm Module
The object alarm module provides an 8-volt reference and a low reference to the four object alarm sensors. The object alarm module receives individual signals from each of the four sensors and determines the location and distance of an object based on these inputs. When an object is detected, the object alarm module will send a serial data message to the radio requesting an audible alert.
Object Alarm Sensor
The object alarm sensors are located in the rear bumper of the vehicle. The sensors are used to determine the distance between an object and the rear bumper. Each sensor emits an ultrasonic frequency which is reflected off an object located behind the vehicle. These reflections are received by the sensors. The time difference between when the frequency was emitted and when the reflection is received, known as sensor echo, is used to determine the distance to the object. The sensors report this information to the object alarm module.
Rear Parking Assist Operation
When the vehicle is first placed into reverse, an audible beep will sound to indicate the system is working.
When backing up at speed of less than 8 km/h (5 mph), the system is constantly monitoring for object of interest located behind the vehicle. 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 or underneath the vehicle. If an object is detected within 2.5 m (8 ft) away from the rear bumper, there will be an audible beep out of the speakers. As the vehicle gets closer to an object, the time between the beeps becomes shorter. If the vehicle stops and there is an object within 2.5 m (8 ft) away from the rear bumper the beeping will stop after 5 seconds. When the distance between the object and the vehicle starts to decrease again the beeping will start again.
If the parking assist system detects a malfunction when the vehicle is placed into reverse there will be no audible beep and a DTC will be stored. The object alarm module will send a serial data message to the instrument panel cluster (IPC) to display the SERVICE PARK ASSIST message on the driver information center (DIC).
See also:
• Component Connector End Views