For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningSafety System Check
Now and then, check that the safety belt reminder light, safety belts, buckles,
latch plates, retractors, and anchorages are all working properly.
Look for any other loose or damaged safety belt system parts that might keep
a safety belt system from doing its job. See your dealer to have it rep ...
Removal Procedure
Warning: Refer to Approved Equipment for Collision Repair Warning in the
Preface section.
Warning: Refer to Glass and Sheet Metal Handling Warning in the Preface section.
Disable the SIR System. Refer to SIR Disabling and Enabling.
Disconnect the negative battery cable. Refer to Battery N ...
Vehicle Access
Specifications
Door Lock/Indicator Schematics
Door Control Module Schematics
Release Systems Schematics
Fuel Tank Filler Door Lock Actuator Replacement
Preliminary Procedure
Remove the fuel tank filler housing. Refer to Fuel Tank Filler Pipe Housing ...