GM Service Manual Online
For 1990-2009 cars only
Liftgate Ajar Switch: The scan tool displays Liftgate Closed/Trunk Ajar. The scan tool displays Trunk Ajar when the liftgate is open.

Trunk Motor:: The scan tool displays On/Off. The scan tool will display the state of the liftgate release.

Liftgate Release Solenoid: The scan tool displays On/Off. The scan tool momentarily displays On when the liftgate release is commanded ON.

Liftgate Release Switch: The scan tool displays Active/Inactive. The scan tool displays active when the liftgate release switch is depressed.