Some owners of 2009 Buick Enclave; Cadillac Escalade, Escalade ESV, Escalade EXT; Chevy Avalanche, Silverado, Suburban, Tahoe, Traverse; GMC Acadia, Sierra, Yukon, Yukon Denali, Yukon XL, Yukon Denali XL; or Saturn Outlook vehicles may comment that the rear parking assist system is inoperative. They may also state that either “Park Assist Off” or “Service Park Assist” messages may be displayed.
GM Engineering is attempting to determine the root cause of this condition. Engineering is seeing an increase in rear object sensor and rear object alarm module replacement. A high percentage of these parts returned to the WPC (warranty parts center) show no trouble found. Engineering has a need to gather information on vehicles that may exhibit this condition. As a result, this information will be used to “root cause” the customer concern and develop a field fix.
If a vehicle is encountered with this concern, perform the diagnosis using either the Parking Assist System Malfunction or the specific DTC based on the diagnostic system check in SI. It may be helpful to reference PIT4828 (Park Assist Off Message on DIC.”
Important: If the sensor is removed, note the position of the sensor alignment marks as shown in the photos here.
If diagnosis leads to replacement of the rear object sensor or rear object alarm module, fill out the following questionnaire and fax this to 586-492-4539, attention to GM Engineer Becky.