GMC Sierra Denali 2017 Owner's Manual page 101

100 Seats and Restraints
airbag status indicator should
light and stay lit when you start
the vehicle. See Passenger
Airbag Status Indicator 0 132.
2. Put the child restraint on
the seat.
3. Pick up the latch plate, and run
the lap and shoulder portions
of the vehicle's safety belt
through or around the restraint.
The child restraint instructions
will show you how.
Tilt the latch plate to adjust the
belt, if needed.
4. Push the latch plate into the
buckle until it clicks.
Position the release button,
away from the child restraint
system, so that the safety belt
could be quickly unbuckled if
necessary.
5. Pull the shoulder belt all the
way out of the retractor to set
the lock. When the retractor
lock is set, the belt can be
tightened but not pulled out of
the retractor.