False Park Assist alerts (Fig. 20) may occur on some 2019-2021 Silverado and Sierra trucks when there is not an object in front and/or behind the vehicle. As a result of the alert, the system may disable itself and a Park Assist Off message may be displayed on the Driver Information Center (DIC). The indicator in the Park Assist switch also will be disabled.
Fig. 20
Depending on the way the Park Assist sensor and/or bezel (Fig. 21) is mounted or painted, the sensor can ground out or pick up normal vehicle vibrations that may be interpreted as an object. If the sensor is properly mounted and isolated from the vehicle, these normal vehicle vibrations would not be picked up the sensor. Since the sensor is working normally, no DTCs will be set.
Fig. 21
识别传感器
There are several possible items to check if this condition is present and to determine which sensor may need repairs.
Disable History– Using GDS2, go into Module Diagnostic/Park Assist Module/Data Display/Parking Assist Disable History 1-4 and 5-7 Data and view the disable history. If the disable history shows “Trailer or Other Object Attached,” it is a good indication there could be an issue with a Park Assist sensor(s) grounding out or getting squeezed and picking up normal vibrations. Don’t overlook obvious things, such as a trailer hitch installed or anything else attached to the vehicle.
TIP:If the disable history shows “Manual Disable,” it may be due to the customer turning off the system. In an effort to make the Park Assist system operational, a customer may try cycling the Park Assist manual disable switch.
Sensor Location- 请咨询客户如果在DIC中显示出在检测到误报时的辅助显示。使用此信息来帮助缩小应检查哪些传感器。例如，如果公园辅助显示器错误地指示车辆左前部的物体，请检查左前方园区辅助传感器/挡板。
GDS2 Parameters- 在带有前后公园辅助的车辆上显示了园区辅助消息，请使用GDS2查看模块诊断/公园辅助模块/数据显示/停车辅助系统数据，并监视“附加对象检测到的正面”和“检测到的附加对象”后方“参数。如果显示停放辅助关闭消息时，其中一个参数是“活动”，它可以帮助确定问题是否具有前部或后传感器/挡板。
TIP:当车辆转移到反向时，前台和后园辅助传感器（如果配备）都是有效的。此外，在向前行驶时，系统确定是否有任何内容附在车辆的前部或后部。
Sensor Repairs
Once it has been determined which sensor(s) to inspect further, check the Park Assist sensor and bezel for any damage. Look for any stone chips, paint chips or dents as well as any issues with the silicone ring, including proper ring installation. (Fig. 22) Repair as necessary. These inspections may require the bumper to be removed.
Fig. 22
检查公园辅助传感器挡板是否正确安装在保险杠孔中。如果挡板未正确安装，它可能导致传感器接地或传感器被挤压。检查将边框固定到保险杠的所有四个锁定标签都完全啮合。（图23）如果选项卡未完全啮合，请确定防止标签从接合的内容，例如过多的涂料或塑料闪烁。除非它们损坏，否则请勿更换传感器或挡板。
Fig. 23
If the Park Assist sensors have been painted, check that the tip of the sensor is isolated from the sensor body by the internal decoupling ring. (Fig. 24) Any paint or clear coat that has run down the side of the sensor’s tip into the gap between the body and sensor tip may cause the sensor to ground out.
Fig 24
For additional details on Park Assist sensor diagnosis and repairs, refer to #PIT5836.
– Thanks to Jim Will
