Parking Aid - System Operation and Component Description: Notes
System Operation
Parking Aid - Audible
System Diagram
Network Message Chart
PAM Network Input Messages
| Broadcast Message | Originating Module | Message Purpose |
|---|---|---|
| Ignition key type | BCM | Used to disable the parking aid menus if a MyKey® is in use. |
| Outside air temperature | FCIM | Used to temperature compensate the parking aid sensor signal using HVAC Ambient Temperature input. |
| Rear parking aid request | IPC | |
| Reverse gear state | PAM | Used to enable the parking aid only when the gear lever is in reverse gear position. |
| Trailer connected status | TRM | Used to disable the rear parking aid when a trailer is electrically to the vehicle. |
| Vehicle speed | PCM | Used to disable the parking aid if the vehicle speed exceeds the preset threshold. |
| Wheel rotation counts | ABS module | Used to detect whether the vehicle is moving or in standstill. |
IPC Network Input Messages
| Broadcast Message | Originating Module | Message Purpose |
|---|---|---|
| Parking aid chime request | PAM | Used to command parking aid warning tones through the audio system speakers. |
| Parking aid audio mute request | PAM | Used to mute the audio when the parking aid chime is requested. |
| Parking aid chime status | PAM | Used to command parking aid warning tones through the audio system speakers. |
| Parking aid fault Status | PAM | Used to generate a fault message in the IPC. |
| Parking aid message center data | PAM | Used to generate the message center display in the IPC. |
| Parking aid switch status | PAM | Used by the IPC for the Parking aid status. |
ACM Network Input Messages
| Broadcast Message | Originating Module | Message Purpose |
|---|---|---|
| Chime control | IPC | Used to generate the requested chime. |
| Chime source | IPC | Used to generate the requested chime. |
Parking Aid System Operation
The rear parking aid system is activated by the PAM when the transmission is shifted into reverse. The PAM calculates the distance to an object within a 170 degree semicircular area (azimuth) around the rear of the vehicle. The parking aid system calculates the distance to an object around the rear of the vehicle using 4 ultrasonic sensors.
The rear outer parking aid sensors can detect objects approximately 60 cm (24 in) from the rear of the vehicle, or 30 cm (12 in) to the side of the rear bumper. The rear inner parking aid sensors can detect objects approximately 180 cm (71 in) from the rear of the vehicle. Objects must be at least 30 cm (12 in) above the ground to be detected by the parking aid system.
The rear sensors are only active when the transmission is in reverse (R), as the vehicle moves closer to the obstacle. The frequency of the audible warning increases. The warning sounds continuously when the obstacle is less than 30 cm (12 in) away. If a stationary or receding object is detected farther than 30 cm (12 in) from the side your vehicle the tone sounds for only three seconds. Once the system detects an object approaching, the warning sounds again.
The system detects certain objects while the transmission is in reverse (R) and the vehicle is:
- Moving toward a stationary object
- Not moving and a moving object is approaching the vehicle
- Moving and a moving object is approaching the vehicle
The parking aid system can be deactivated using the display menu, or the pop-up message displayed in the message center after the transmission is shifted into reverse gear. The parking aid system cannot be disabled in this manner if a MyKey® is in use. The parking aid system is disabled and cannot be activated on vehicles equipped with a trailer towing package whenever a trailer is electrically coupled to the vehicle.
Parking Aid Alert
When an object is detected by the parking aid system and the transmission is in reverse, the IPC performs an arbitration function to prioritize the tone. The IPC built in logic determines when to mute the audio, and then sends a tone request message to the ACM to reduce the current audio volume and sound the parking aid tone through the rear audio system speakers. The alert tone frequency increases as the vehicle gets closer to an obstacle. When an object is detected within 30 cm (12 in) of the sensors, the alert tone becomes continuous. Objects detected outside the continuous tone area to the side of the vehicle generate a warning tone for 3 seconds. The warning tones are prioritized to the closest object.
The rear parking aid system standstill strategy provides audio warnings when the vehicle is stationary, with the transmission in reverse, and the detected obstacle is less than 30 cm (12 in) away from the rear bumper.