GMC 2005 Canyon - Manual (Page 29)

To unlatch the belt, just push the button on the buckle.
The belt should go back out of the way.
Before you close the door, be sure the belt is out of the
way. If you slam the door on it, you can damage
both the belt and your vehicle.
Shoulder Belt Height Adjustment
Before you begin to drive, move the shoulder belt height
adjuster to the height that is right for you.
Adjust the height so that the shoulder portion of the
belt is centered on your shoulder. The belt should
be away from your face and neck, but not falling off
your shoulder.
To move it up or down,
squeeze the release
buttons (A) together and
move the height adjuster
to the desired position.
After you move the adjuster
to where you want it, try to
move it down without
squeezing the release
buttons to make sure it has
locked into position.
1-23