Principles of Operation
Parking Aid
Principles of Operation
NOTE: The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM).
The parking aid system detects objects behind the vehicle when the REVERSE (R) gear is selected. The Parking Aid Module (PAM) calculates the distance to an object by the use of 4 ultrasonic sensors mounted in the rear bumper. The PAM does this by calculating the distance to an object within the 170 degree semicircular area around the rear of the vehicle.
The parking aid sensors detect objects approximately 1.8 m (5.9 ft) from the rear of the vehicle, 50 cm (1.6 ft) from the rear side of the vehicle, and 16 cm (6 in) above the ground. A variable rate warning tone is generated from a parking aid speaker attached to the PAM. The parking aid speaker increases its warning tone rate as the vehicle gets closer to an obstacle. When an object is detected within 25 cm (10 in) of the sensors, the warning tone becomes continuous.
The rear parking aid system is enabled when the ignition switch is in the RUN position and the REVERSE (R) gear is selected. The parking aid system can be disabled with a control in the Instrument Cluster (IC) message center. The parking aid system is disabled if a fault is detected in any of the sensors, the parking aid speaker or the PAM. This condition is indicated by the parking aid disabled warning in the message center. The PAM is on the High Speed Controller Area Network (HS-CAN) and can be diagnosed with a scan tool.
Active Park Assist System
The active park assist system detects available parking space and automatically steers the vehicle in the parking space without the driver touching the steering wheel. The driver controls the accelerator, transmission selection and the vehicle brakes. The system visually and/or audibly instructs the driver throughout the procedure to safely park the vehicle. The PAM controls the active park assist system. The system uses 2 long range ultrasonic sensors that are hardwired to the PAM to detect the available parking space for the vehicle. The PAM uses the HS-CAN to send and receive network messages to control the active park assist system. Refer to Collision Avoidance and Parking Assist Systems for active park assist information.
Network Communication
NOTE: Both the Medium Speed Controller Area Network (MS-CAN) and the HS-CAN are used for intermodule communication. A gateway message is transferred from one network to another network through the Instrument Cluster (IC). For a complete list of Controller Area Network (CAN) multiplex messages, refer to Information Bus.
Parking Aid Module (PAM) Network Communication Messages