GMC Envoy Owner's Manual page 54

7. Push and pull the child restraint in different
directions to be sure it is secure.
8. If the airbag is off, the off indicator in the inside
rearview mirror will be lit and stay lit when the
key is turned to RUN or START.
If a child restraint has been installed and the on
indicator is lit, turn the vehicle off. Remove the child
restraint from the vehicle and reinstall the child restraint.
If after reinstalling the child restraint and restarting
the vehicle, the on indicator is still lit, check to make
sure that the vehicle's seatback is not pressing the child
restraint into the seat cushion. If this happens, slightly
recline the vehicle's seatback and adjust the seat
cushion if possible. Also make sure the child restraint is
not trapped under the vehicle head restraint. If this
happens, adjust the head restraint.
If the on indicator is still lit, secure the child in the child
restraint in a rear seat position in the vehicle and
check with your dealer.
To remove the child restraint, just unbuckle the vehicle's
safety belt and let it go back all the way. The safety
belt will move freely again and be ready to work for an
adult or larger child passenger.
1-47