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For 1990-2009 cars only

Info - Global Position Sensor (GPS) Performance Degradation

Subject:Global Position Sensor (GPS) Performance Degradation

Models:1996-2005 Passenger Cars and Trucks
2003-2005 HUMMER H2
2002-2005 Saturn Vehicles
with Navigation Systems and/or OnStar®



This bulletin is being revised to include additional information. Please discard Corporate Bulletin Number 00-08-46-003A (Section 08 - Body and Accessories).


Navigation and OnStar® systems require a GPS antenna in order to function properly. This antenna may be located inside the vehicle. If the GPS antenna is located inside the vehicle, performance of the system may be compromised by window tinting film.

If the GPS system performance is in question and the vehicle has window tinting, a quick diagnostic check can be made by temporarily moving the GPS antenna to an external vehicle surface, such as the decklid or roof. If the GPS function of the navigation or OnStar® system operates normally with the antenna relocated , the repair would not be considered a warranty repair. The subsequent repair procedure or GPS placement would be up to the customer.

Some vehicles have the GPS antenna located on the rear window shelf. Objects placed on the rear window shelf, such as tissue boxes, books, dolls, etc., also have the potential to interfere with GPS performance.

Warranty Information

Repairs made to the vehicle navigation and/or OnStar® system, which are the result of window tinting, are not considered warranty repairs.