GMC Jimmy 2004 Owner's Manual page 13

To raise the seatbacks, lift up the seatbacks and pull
up. Push and pull on the seatbacks to check that
the latches have locked in the upright position. If they
haven't, see your dealer for service.
To return the head restraints to the upright position,
reach behind the seats and pull the head restraint
up until it locks into position.
On two-door models with an inside mounted spare tire,
the driver's side rear seat head restraint must be
lifted and held upright as the seatback is raised.
Otherwise, the head restraint will hit the spare tire
and prevent the seatback from properly latching.
Push and pull on the head restraints to check that they
have locked in the upright position. If they haven't,
see your dealer for service.
CAUTION:
{
If the seatback isn't locked, it could move
forward in a sudden stop or crash. That could
cause injury to the person sitting there. Always
press rearward on the seatback to be sure it
is locked.
CAUTION:
{
A safety belt that is improperly routed, not
properly attached, or twisted won't provide
the protection needed in a crash. The person
wearing the belt could be seriously injured.
After raising the rear seatback, always check
to be sure that the safety belts are properly
routed and attached, and are not twisted.
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