GM Service Manual Online
For 1990-2009 cars only
Figure 1:

Garage Door Opener


Object Number: 1874221  Size: FS
Master Electrical Component List
Garage Door Opener Description and Operation
Control Module References
Keyless Entry
Figure 2:

Keyless Entry


Object Number: 1874223  Size: FS
Master Electrical Component List
Keyless Entry System Description and Operation without Accessory 2 Way Remote
Control Module References
Garage Door Opener