Ultrasonic Rear Park Assist Operation
The ultrasonic rear park assist system senses how close the vehicle is to an object. The distance is determined by the 4 object sensors located in the rear bumper. The object detection system will notify the driver when backing up at speeds less than 8 km/h
(5 mph). The object detection system will use the rear parking assist (RPA) display and the radio speakers for notification.
When the ignition is ON and the vehicle is placed into reverse, the object detection system performs a bulb check. During the bulb check, the 3 indicators on the RPA will illuminate for approximately 2 seconds to indicate that the system is working.
The object detection system performs a bulb check and operates when the following conditions are present:
| • | The vehicle is placed in REVERSE (R) for rear parking aid. |
| • | The vehicle speed is less than 5 km/h (3 mph). At speeds greater than 5 km/h (3 mph), the object detection system is disabled. The red indicator flashes to warn the driver that the object detection system is disabled. |
The object detection system senses how close the vehicle is to an object. The distance is determined by the 4 object sensors located on the rear bumper. When the system detects an object, one of the following will occur:
| • | If the object is less than 0.3 m (11 in) away from the vehicle, the amber outside, amber middle, and the red outside indicators flash and the chime sounds continuously for 3 seconds. |
| • | If the object is less than 0.3-0.5 m (11-20 in) away from the vehicle, the amber outside, amber middle, and the red outside indicators are ON. |
| • | If the object is 0.5-1.0 m (20-40 in) away from the vehicle, the amber outside, and the amber middle indicators are ON. |
| • | If the object is 1-2.3 m (40-91 in) away from the vehicle, the amber outside indicator is ON with a single chime when the object is first detected. |
Object detection system can detect objects 7.6 cm (3 in) wide and at least 25.4 cm (10 in) tall. It cannot detect objects above the level of the roof.
If the object detection system detects a malfunction, a diagnostic trouble code (DTC) will be stored and the object detection system will send a serial data communication message to the instrument panel (I/P) to SERVICE PARK ASSIST message on the driver
information center (DIC). Then the chime will sound and the red indicator on the information telltale center will be lit continuously. The red LED in the rear display will be lit, notifying the driver that a malfunction exists. Message will clear once the driver
acknowledges it.
Each object sensor is a three wire sensor that is both a transmitter and a receiver that comprises a signal circuit, a low reference circuit, and an 8-volt supply voltage circuit. The rear object control module supplies 8 volts to the object sensors
via the object sensor supply voltage circuit and provides ground via the low reference circuit. The rear object control module triggers the sensors in a sequential loop and after each sensor transmits, the rear object control module uses the echo or signal return
to calculate the distance and position of an object from the rear bumper. The rear object control module directly controls the RPA display.
Object Alarm System DIC Messages
SERVICE PARK ASSIST
The driver information center (DIC) displays SERVICE PARK ASSIST when the object alarm module detects a malfunction in the object detection system and sends a request to the DIC for display of the message. The DIC also displays SERVICE PARK ASSIST when
there is a loss of communication with the object alarm module.
PARK ASSIST OFF
The PARK ASSIST OFF message is displayed in the DIC when the object alarm system is disabled due to conditions that disable or inhibit the system. The red LED in the rear display, as well as, the telltale in the switch will be lit, notifying the driver
the PARK ASSIST system is disabled. The object alarm module requests the DIC via the serial data circuit to display PARK ASSIST OFF when it detects that one of the following conditions is true:
| • | The object alarm system is disabled through DIC vehicle customization feature. Refer to the Owners Manual for more information. |
| • | An object is attached to the rear of the vehicle, such as a trailer, bicycle rack, or hitch receiver. |
| • | An object is hanging out of the endgate. |
| • | The park brake is not fully released. |
| • | The system receives vibrations from a large nearby vehicle or from a heavy equipment such as a jackhammer. |
In the case of objects attached to the rear of the vehicle such as a trailer, hitch receiver, or a bicycle rack, or objects hanging out of the endgate, the rear parking assist (RPA) will have an Automatic Object induced disable feature where the RPA will
determine if the rear object is moving with the vehicle. If the RPA detects such a condition, the park assist will be disabled. The PARK ASSIST OFF message will continue to be displayed until the trailer hitch receiver is removed and the vehicle is driven forward
above 24 km/h (15 mph).
