Diagnostic Aids
WARNING: This page is about a different car, the 2009 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.
The scan tool Park Assist Disable History parameters are a list of the seven previous reasons the park assist system was disabled. These parameters may help in the diagnosis of an intermittent concern or a customer concern which is the result of normal system operation. The following is a brief description of potential causes which may aid in diagnosis:
- Manual Disable - The park assist system has been disabled by the vehicle operator through the DIC.
- Park Brake - The vehicle parking brake is applied or a malfunction exists within the parking brake system.
- Hitch/Object Attached - The object alarm module is detecting an object that is attached to the vehicle. Common items such as a hitch receiver, trailer, or a bicycle rack may cause this concern. Additionally, damage to the rear of the vehicle or a misaligned sensor may cause this concern. If the vehicle is damaged in a manner that causes the sensor to detect the bumper itself, the object alarm module will interpret this as an attached object and disable the system. Carefully inspect the bumper, bumper mounting surface, and sensor retainers before continuing with normal diagnosis.
- Reverse Overspeed - The vehicle is traveling too fast in reverse at speeds of greater than 8 km/h (5 mph).
- Sensor Disturbance - An outside interference is causing sensor movement. Such interference may be caused a heavy pounding, like that of a nearby jackhammer, or large changes in pressure, such as a large truck's air brakes.
- Snow/Ice/Mud - One or more of the sensors is being blocked by snow, mud, ice, or other debris.
- Sensor Ring Time - Each of the sensors emits an ultrasonic frequency. This frequency is reflected off of nearby objects, bouncing it back towards the vehicle bumper where it is received by the sensor. The time between the sensor emitting the frequency and the sensor receiving the reflection, known as sensor ring time, is used to determine the distance of nearby objects. Excessive paint thickness on a sensor may cause an excessive sensor ring time. When replacing or refinishing a sensor, do not apply an excessive amount of paint or clear coat.