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Circuit/System Description
The body control module (BCM) supplies B+ to the rearview camera when the transmission is placed into reverse.
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.
When the ignition is turned ON, the parking assist control module and the frontview camera module receives the vehicle identification number (VIN) from the body control module. The modules 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 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 ultrasonic 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 sensors located in the rear bumper. The parking assist system will notify the driver using an audible signal through the radio.
When the transmission is placed into REVERSE, a 12 volt signal is sent to the rearview camera and rearview mirror indicating that the vehicle is in reverse and image display is requested. Ignition voltage and ground are supplied to the rearview camera. The rearview mirror is supplied ignition voltage and a common ground. The rearview camera sends video information to the LCD display located in the rearview mirror. The video signal is shielded to reduce electronic interference which may degrade the video signal and cause a distorted or degraded image.
Rear Vision Camera System Operation
The rear vision camera system consists of a video camera located at the rear of the vehicle and a 3.5 inch LCD display integral to the inside rearview mirror (ISRVM).
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 LCD display in the inside rearview mirror. 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
- 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 temperatures or extreme temperature changes