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. |
| Ignition status | BCM | Used to communicate the ignition switch state. |
| Outside air temperature | FCIM | Used to temperature compensate the parking aid sensor data. |
| Parking aid enable/disable request | IPC | Used to enable or disable the parking aid based on driver input. |
| Gear position (automatic transmission) | PCM | Used to enable or disable the parking aid depending on the selector lever position. |
| Reverse gear (manual transmission) | PCM | Used to enable or disable the parking aid depending on the gearshift lever position. |
| Vehicle speed | PCM | Used to disable and enable the parking aid based on vehicle speed. |
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 fault status | PAM | Used to generate the parking aid warning message and chime in the event of a parking aid system concern. |
ACM and DSP Network Input Messages
| Broadcast Message | Originating Module | Message Purpose |
|---|---|---|
| IPC chime request | IPC | Input used to control the audio chime output. This message contains the parking aid chime request data. |
Audible Parking Aid System Operation
The PAM calculates the distance to an object within a 170 degree semicircular area (azimuth) around the rear of the vehicle when the selector lever (automatic transmission) or gearshift lever (manual transmission) is in reverse. When the system is active and an object is detected within the rear parking aid azimuth around the rear of the vehicle, a variable rate warning tone is sounded through the rear audio system speakers.
The rear 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 24 in (60 cm) from the rear of the vehicle. The rear inner parking aid sensors can detect objects approximately 70 in (177 cm) from the rear of the vehicle. Objects that are approximately 14 in (35 cm) to the side of the rear bumper can also be detected by these sensors. Objects must be 12 in (30 cm) above the ground to be detected by the rear parking aid system. The PAM supplies voltage and ground to the rear ultrasonic sensors while monitoring a signal return circuit from each sensor. The 4 sensors share common voltage and ground circuits.
Only objects that reflect a sufficient amount of sound waves are detected by the rear parking aid sensors. The surface properties, size and composition of an object can affect the ability of the parking aid system to detect the object. Incorrect sensor alignment or installation, dirt or ice covered sensors, heavy rain and snow can also cause objects not to be detected.
The rear parking aid system can be disabled through the message center. The system remains disabled until enable through the message center or the ignition is turned off and back on. When a MyKey ® restricted key is in use, the rear parking aid can not be disabled.
Parking Aid Audible Alert
When the selector lever (automatic transmission) or gearshift lever (manual transmission) is in reverse and an object has been detected by the rear parking aid system, the IPC performs an arbitration function to prioritize the chime. The IPC built in logic determines when to mute the audio then sends a chime request message to the ACM (with 4.2 in (107 mm) display) or DSP (with 8 in (203 mm) touchscreen) to reduce the current audio volume and sound the parking aid chime 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 12 in (30 cm) 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 12 in (30 cm) away from the rear bumper.
Component Description
Parking Aid Sensors
The parking aid sensors are wide beam ultrasonic sensors. When the ignition is on, the sensors continuously send out ultrasonic signals to detect objects and communicate the information back to the PAM.
PAM
The PAM supplies voltage and ground to the rear ultrasonic sensors while monitoring a signal return circuit from each sensor. When an object is detected by the sensors and the rear parking aid system is active, the PAM calculates and reports, via audio system tones, the distance between the rear bumper of the vehicle and an object.
The PAM is integral to the BCM but communicates as a separate node on the HS-CAN1.
The BCM requires PMI when replaced.