GMC Yukon XL 2015 Owner's Manual page 54

The modes are:
MAX: Opens to maximum
height.
3/4: Opens to a reduced height
that can be set from 3/4 to fully
open. Use to prevent the liftgate
from opening into overhead
objects such as a garage door or
roof-mounted cargo. The liftgate
can be opened all the way
manuallly.
OFF: Opens manually only.
To open or close the liftgate, select
MAX or 3/4 mode and then:
b
Press twice quickly on the
RKE transmitter until the liftgate
moves.
8
Press on the overhead
console. The driver door must
be unlocked.
Press the touch pad on the
outside liftgate handle after
unlocking all doors. If equipped
with Keyless Access, a locked
vehicle can be opened if the
RKE transmitter is within 1 m
(3 ft) of the touch pad.
Press on the bottom edge of
the liftgate next to the latch to
close.
Press any liftgate button, the touch
b
pad, or on the RKE transmitter
while the liftgate is moving to stop it.
Pressing again restarts the
operation in the reverse direction.
The touch pad on the liftgate handle
cannot be used to close the liftgate.
Keys, Doors, and Windows
Do not manually force the liftgate to
open or close during a power cycle.
The power liftgate may be
temporarily disabled in extremely
low temperatures, or after repeated
power cycling over a short period of
time. If this occurs, the liftgate can
still be operated manually. Select
OFF on the liftgate switch.
If the vehicle is shifted out of
P (Park) while the power function is
in progress, the liftgate will continue
to completion. If the vehicle is
accelerated before the liftgate has
completed moving, the liftgate may
stop or reverse direction. Make sure
the liftgate is closed and latched
before driving.
If the power liftgate support strut
has lost pressure, the turn signals
will flash and a chime will sound
while the liftgate automatically
closes. See your dealer for service
before using the power liftgate.
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