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Active Park Assist




Active Park Assist

Principles of Operation

NOTE: The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM).

The Parking Aid Module (PAM) communicates with several modules over the High Speed Controller Area Network (HS-CAN), via network messaging, in order to control the functions of the active park assist system.

When the active park assist switch is pressed, a ground signal input is sent to the PAM (Parking Aid Module) enabling the active park assist system. The PAM (Parking Aid Module) sends a HS-CAN (High Speed Controller Area Network) message to the Instrument Panel Cluster (IPC) and the IPC (Instrument Panel Cluster) message center displays the message "ACTIVE PARK SEARCHING". The IPC (Instrument Panel Cluster) gateways the turn signal input from the multifunction switch to the PAM (Parking Aid Module) via a network message to determine the active side of the vehicle. The arrow symbol "〈〈 >>" in the message center indicates the active side of the vehicle is being parked. If the turn signal is not selected, the active park assist system defaults to searching and parking on the passenger side of the vehicle.

The 2 long range ultrasonic active park assist sensors that are located in the left and right side of the front bumper cover are continuously sending out ultrasonic signals to detect an available parking space and communicating the information back to the PAM (Parking Aid Module). This occurs if the vehicle is moving regardless if the operator has pressed the active park assist switch. The active park assist sensor distance detection range is approximately 390 cm (154 in), projecting outward from the side of the vehicle. For information on range detection, refer to Azimuth System Check .

Each available parking space is scanned on both sides of the vehicle as the operator drives by. The active park assist system only offers the available spaces that are on the active side of the vehicle. The system measures the available parking spaces and its surroundings as the operator drives by to determine if the vehicle can be maneuvered into the available parking space. This is determined from the input signals sent to the PAM (Parking Aid Module) from the active park assist sensors. The minimum length that the active park assist system offers is approximately 1.2 times the length of the vehicle.

Once a parking space is located and the system has been activated by the operator pressing the active park assist switch, the PAM (Parking Aid Module) sends a HS-CAN (High Speed Controller Area Network) message to the IPC (Instrument Panel Cluster) and the message center displays "SPACE FOUND PULL FORWARD" followed by an audible chime from the IPC (Instrument Panel Cluster). The operator pulls the vehicle forward and the IPC (Instrument Panel Cluster) message center displays the message "SPACE FOUND STOP". Once the operator has stopped the vehicle, the IPC (Instrument Panel Cluster) message center displays the message "REMOVE HANDS PUT IN REVERSE". The active park assist system takes control of the steering after the transaxle is placed in REVERSE (R) and the Power Steering Control Module (PSCM) does not detect the operator input torque on the steering wheel.

After the PAM (Parking Aid Module) has received these inputs it sends steering command messages to the PSCM (Power Steering Control Module) over the HS-CAN (High Speed Controller Area Network). The PSCM (Power Steering Control Module) is attached to the Electronic Power Assist Steering (EPAS) gear assembly and is used to control the steering portion of the active park assist system and monitors the operator input torque to the steering wheel. For information on the EPAS (Electronic Power Assist Steering) system, refer to Steering System.

The PSCM (Power Steering Control Module) and the PAM (Parking Aid Module) utilizes steering angle inputs that are transmitted by the Steering Angle Sensor Module (SASM) for steering wheel position. The vehicle wheel roll count, wheel direction and wheel speed sensor inputs are transmitted by the ABS module over the HS-CAN (High Speed Controller Area Network) to the PAM (Parking Aid Module) and/or the PSCM (Power Steering Control Module). The vehicle speed and transaxle position are transmitted by the PCM over the HS-CAN (High Speed Controller Area Network) to the PAM (Parking Aid Module) and/or the PSCM (Power Steering Control Module). The PAM (Parking Aid Module) uses that data to calculate vehicle position and distance in relation to the parking space. The inputs are used by the PAM (Parking Aid Module) to command the steering system to assist with the steering wheel control to maneuver the vehicle into the parking space.

If the PSCM (Power Steering Control Module), the PCM, the ABS module, and/or the SASM (Steering Angle Sensor Module) malfunction, the active park assist system is disabled or prevents the system from activating. The message "ACTIVE PARK FAULT" or "ACTIVE PARK NOT AVAILABLE" is displayed in the IPC (Instrument Panel Cluster) message center and a DTC is set in the PAM (Parking Aid Module).

The operator has full control of gear-shifting, the accelerator and the brake pedal. The IPC (Instrument Panel Cluster) message center displays the message "BACK UP USE CAUTION" as the vehicle enters the parking space.

The rear parking aid sensors are used to detect a vehicle or object located behind the vehicle in the parking space. The PAM (Parking Aid Module) determines the distance to the rear of the vehicle from the input signal from the rear parking aid sensors. The rear parking aid speaker sounds a continuous tone when the rear bumper of vehicle is approximately 30 cm (12 in) from the vehicle to the rear and the message in the message center displays "PULL FORWARD USE CAUTION" followed by an audible chime from the IPC (Instrument Panel Cluster).

When the transaxle is placed in DRIVE (D), the PAM (Parking Aid Module) receives the drive gear input message over the HS-CAN (High Speed Controller Area Network) from the PCM. The active park assist system continues to control the steering as the operator moves the vehicle forward. The front parking aid sensors are used to detect a vehicle or object located in front of the vehicle in the parking space. The PAM (Parking Aid Module) determines the distance to the front of the vehicle from the input signal from the front parking aid sensors. When the front bumper of the vehicle is approximately 30 cm (12 in) from the front vehicle the front parking aid speaker sounds a continuous tone and the IPC (Instrument Panel Cluster) message center displays the message "BACK UP SLOWLY USE CAUTION" followed by an audible chime from the IPC (Instrument Panel Cluster). The active park assist system may offer subsequent backward and forward maneuvers before finalizing the parking sequence.

The PAM (Parking Aid Module) determines that the active park maneuvers are completed based on the final vehicle alignment. The vehicle should be located approximately 0-30 cm (0-12 in) from the street curb if a curb is detected, otherwise the system aligns the vehicle to the front vehicle. The IPC (Instrument Panel Cluster) message center displays the message "ACTIVE PARK FINISHED" followed by an audible chime from the IPC (Instrument Panel Cluster).

Pressing and releasing the active park assist switch at anytime disables the active park assist system. If the system is disabled by the operator after the system starts to control the steering, the IPC (Instrument Panel Cluster) message center displays the message "ACTIVE PARK CANCELLED" followed by a warning chime.

The following conditions can result in the active park assist system to be cancelled:





The active park assist system is not available if the following conditions exist:

- A vehicle attachment is detected, such as a trailer or bike rack, by the reverse parking aid system.

- Any door (except the driver's door) is ajar.

- AdvanceTrac(R) has been deactivated by the operator before activating the active park assist system or an AdvanceTrac(R) or ABS event occurs when the active park assist system is activated.

The IPC (Instrument Panel Cluster) message center displays the message "ACTIVE PARK NOT AVAILABLE" followed by an audible chime.

The following conditions can cause the active park assist system to incorrectly align the vehicle in the selected parking space:

- A spare tire is used or one of the vehicles tires has significantly more or less tread wear than the other tires.

- The factory-installed tire sizes are not used on the vehicle.

- Poor weather conditions, such as heavy rain or snow.

- If the active park assist sensors are damaged or obstructed.

- There may be an irregular curb along the parking space.

- The vehicle or objects bordering the space may not be positioned correctly. The system aligns the vehicle to the front vehicle when the curb is not detected.

- The parking space length or parked objects position have changed after the vehicle has passed the parking space.

- The temperature around the vehicle changes quickly such as the vehicle driven from a heated garage into the cold or just leaving a car wash before the system was used.

- One of the parked vehicles has a high attachment, such as a salt spreader or moving truck bed, that the sensors cannot detect.

When a fault is present in the active park assist system, the PAM (Parking Aid Module) sends a network message to the IPC (Instrument Panel Cluster) and the IPC (Instrument Panel Cluster) message center displays the message "ACTIVE PARK FAULT" followed by a warning chime. This disables the active park assist system.

Network Communication

NOTE: Both the Medium Speed Controller Area Network (MS-CAN) and the HS-CAN (High Speed Controller Area Network) are used for intermodule communication. A gateway message is transferred from one network to another through the IPC (Instrument Panel Cluster). Refer to Information Bus for network communication information.

Parking Aid Module (PAM) Network Communication Messages










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