GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
26 Keys, Doors, and Windows
Power Tailgate
{Warning
Make sure there is no one in the way of
the power tailgate as it is opening and
closing, and keep hands away from the
tailgate hinges when in use. You or
others could be injured if caught in the
path of the power tailgate or tailgate
hinges.
Caution
To avoid damage to the tailgate, make
sure the area behind the tailgate is clear
before opening it.
If equipped with a power open/close
tailgate, the tailgate can be opened or
closed in several ways. To open the tailgate,
do one of the following:
.Pressxtwice quickly on the remote
key until the tailgate moves. See Remote
Key Operation 015. If equipped with
Keyless Access, a locked tailgate can be
opened if the remote key is within
1 m (3 ft).
.Press5on the center stack.
.Press the touch pad on the tailgate
handle after unlocking all doors. To close the tailgate, do one of the
following:
.Pressxon the remote key once, then
quickly press and hold
xuntil the
tailgate completely closes. If
xis
released prior to it being fully closed, the
tailgate will reopen.
.Press and hold5on the center stack
until the tailgate is fully closed. If
5
is released prior to the tailgate being
fully closed, it will reopen. A chime will
sound when the tailgate is fully closed.
.Press the touch pad on the tailgate
handle.
A chime sounds and the taillamps flash
during the closing operation. If the warning
chime is not functioning, the tailgate will
not power close. Power opening is still
enabled. See your dealer for service.
The power tailgate may be temporarily
disabled after repeated power cycling over a
short period of time. If this occurs, the
tailgate can still be operated manually.
The vehicle must be in P (Park) to operate
the power tailgate. If the vehicle is shifted
out of P (Park) while the power function is
in progress, the tailgate will continue to
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
Keys, Doors, and Windows 27
completion. If the vehicle is accelerated
while the tailgate is still closing, the tailgate
may stop and reverse direction. Make sure
the tailgate is closed and latched before
driving.
Lift-to-Close Operation
To close the tailgate using the lift-to-close
feature, lift the tailgate from the full-open
position to at least 10 cm (4 in) and hold it
momentarily. Then, the tailgate will start
closing automatically. If the tailgate is lifted
more than halfway between open and close,
then it will not close automatically.Obstacle Detection
If the tailgate encounters an obstacle during
a power open cycle, it will stop on the
obstacle. After removing the obstruction, the
tailgate can be allowed to open. If the
tailgate encounters an obstacle during the
closing cycle, it will stop and reverse to
full open.
If the tailgate encounters multiple obstacles,
the power function will deactivate. After
removing the obstructions, manually close
the tailgate to resume normal power
operation.
Manual Operation
The tailgate can be manually closed from
the full-open position when the tailgate is
lifted in a continuous motion. If the tailgate
motion is stopped between the full-open
and half-closed positions, the lift-to-close
feature can engage and power close the
tailgate. If the touch pad is pressed during
power operation, the tailgate will stop and
allow manual operation. The tailgate must
be held after stopping, or it will continue
to open.
MultiPro Tailgate
{Warning
Make sure there is no one in the way of
the power tailgate as it is opening and
closing, and keep hands away from the
tailgate hinges when in use. You or
others could be injured if caught in the
path of the power tailgate or tailgate
hinges.
Caution
To avoid damage to the tailgate, make
sure the area behind the tailgate is clear
before opening it.
If equipped with this feature, the vehicle
must be in P (Park).
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
28 Keys, Doors, and Windows
Switches in the inner tailgate prevent the
primary tailgate from being opened when
the inner tailgate is not fully closed.
To open the primary tailgate:
.Pressxtwice quickly on the remote
key until the tailgate moves. See Remote
Key Operation 015. If equipped with
Keyless Access, the tailgate can be
opened if the remote key is within
1 m (3 ft).
.Press5on the center stack.
.Press the lower touch pad on the tailgate
handle after unlocking all doors. Use the
top of the tailgate to pull against if
assistance is required.
To close the primary tailgate, firmly push it
upward until it latches. Pull it back to be
sure it is latched securely.
To open the inner tailgate, press the upper
touch pad on the tailgate handle after
unlocking all doors. Pull the top of the
tailgate to open.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
Keys, Doors, and Windows 29
Caution
Do not open the inner tailgate with the
primary tailgate open if there is a hitch
ball or trailer attached. This may damage
the tailgate.
To close the inner tailgate with the primary
tailgate closed, firmly push or pull it upward
until it latches. Pull it back to be sure it is
latched securely.
To close the inner tailgate with the primary
tailgate open:
.Hold the primary tailgate and firmly close
the inner tailgate.
.Raise the inner tailgate so it meets the
primary tailgate and close together at the
same time.
When using the tailgate step as a load stop,
the load must be secured as the load could
shift. See Cargo Tie-Downs 0102.
MultiPro Inner Tailgate Enable/Disable
The MultiPro inner tailgate may be equipped
with an enable/disable feature to prevent
the inner tailgate from being opened when
a hitch or other equipment is installed that
could damage the inner tailgate.
To disable the inner tailgate from opening:
ensure that the remote key is within
1 meter (3 ft) of the rear bumper and then
hold the upper touchpad on the tailgate
handle for up to seven seconds. The tail
lamps will flash to alert you that the inner
gate has been disabled. The inner and outer
tailgate can still be operated like a
traditional tailgate, but the inner gate will
not be able to be opened alone. To enable the inner tailgate function, hold
the upper touchpad on the handle for up to
seven seconds until the tail lamps flash. The
inner tailgate can now be opened separately
from the outer tailgate.
Tailgate Step (Step Mode)
{Warning
To avoid personal injury, keep hands
away from the hinges when operating
the tailgate step.
With the primary and inner tailgates open,
the tailgate step can be lowered to access
the pickup bed.
Using the Step
Caution
When using the tailgate as a step, the
load rating is 170 kg (375 lb), which
includes a person and cargo. Overloading
the tailgate step can cause damage to
the tailgate system.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
30 Keys, Doors, and Windows
.To lower the tailgate step, press the
button at the center of the step. Make
sure it lowers to the fully open position.
.To close the tailgate step, lift it firmly.
Make sure that both side latches are
engaged.
Do not place a load on top of the step when
using it as a load stop.
Using the Assist Handle
The assist handle helps with entering the
pickup box. To use:1. Lift up on the handle until it locks in the open position.
2. To return the assist handle, pull the release lever toward the ball end of the
handle and push the handle back to the
closed position.
Applying Loads to Tailgates
Caution
Do not put ramp loads on the inner
tailgate alone. Damage to the inner
tailgate may occur.
Preferred Method
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
Keys, Doors, and Windows 31
Alternate Method
When applying any load to the tailgate,
distribute the weight evenly across the
width of the tailgate. This applies to all
tailgate types.
.Use a load-distributing member (1).
.Secure the ramp to the bumper (2).
Transporting Items That Can
Catch Fire
{Warning
To avoid personal injury and/or vehicle
damage when transporting items that
can catch fire, such as leaves, mulch, hay,
or cardboard, in the truck bed:
.Make sure items are securely
contained inside the truck bed. Never
allow them to hang over the sides or
fall in between the truck bed and
the cab.
.Never place items between the cab
and the truck bed. They could touch
hot exhaust parts and ignite.
{Warning
Keep cigarettes, sparks, and other ignition
sources away from the area between the
bed of the truck and cab. They could fall
onto the fuel system below and start a
fire. You or others could be injured
and/or the vehicle damaged.
Power Assist Steps
{Warning
To avoid personal injury or property
damage, before entering or exiting the
vehicle, be sure the power assist step is
fully extended. Do not step on the power
assist step while it is moving. Never place
hands or other body parts between the
extended power assist step and the
vehicle.
If equipped, the power assist steps will
deploy when the door is opened and
automatically retract three seconds after the
door is closed. The power assist steps will
retract immediately if the vehicle starts
moving. Check the step position before
exiting the vehicle.
Disable the power assist steps before jacking
or placing any object under the vehicle.
Too much ice buildup may prevent
deployment of the power assist steps. If this
happens, disable the power assist steps,
clear the ice, then enable the assist steps
and confirm normal function prior to use.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
32 Keys, Doors, and Windows
Keep hands, children, pets, objects, and
clothing clear of the power assist steps
when in motion. The steps will reverse
direction if they encounter an obstruction
when opening or closing. Remove the
obstruction, then open and close the door
on the same side to complete the motion of
the assist steps. If the obstruction is not
cleared, the assist steps remain extended
while driving.
Extend or retract both power assist steps
for cleaning through the vehicle settings
menu. To view available settings from the
infotainment screen, touch Settings >
Vehicle > Comfort and Convenience.
Enable/Disable
The power assist steps can be enabled or
disabled through the vehicle settings menu.
To view available settings from the
infotainment screen, touch Settings >
Vehicle > Comfort and Convenience.
Vehicle Security
This vehicle has theft-deterrent features;
however, they do not make the vehicle
impossible to steal.
Vehicle Alarm System
The indicator light, on the instrument panel
near the windshield, indicates the status of
the system.
Off :Alarm system is disarmed.
On Solid : Vehicle is secured during the
delay to arm the system.
Fast Flash : Vehicle is unsecured. A door or
the hood is open.
Slow Flash : Alarm system is armed.
Arming the Alarm System
1. Turn off the vehicle. 2. Lock the vehicle in one of two ways:
.Use the remote key.
.With a door open, pressQon the
interior of the door.
3. After 30 seconds, the alarm system will arm and the indicator light will begin to
slowly flash. Pressing
Qon the remote
key a second time will bypass the
30-second delay and immediately arm
the alarm system.
The vehicle alarm system will not arm if the
doors are locked with the key.
If the driver door is opened without first
unlocking with the remote key, the horn will
chirp and the lights will flash to indicate
pre-alarm. If the vehicle is not started,
or the door is not unlocked by pressing
K
on the remote key during the 10-second
pre-alarm, the alarm will be activated.
The alarm will also be activated if a
passenger door or the hood is opened
without first disarming the system. When
the alarm is activated, the turn signals flash
and the horn sounds for about 30 seconds.
The alarm system will then re-arm to
monitor for the next unauthorized event.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
Keys, Doors, and Windows 33
Disarming the Alarm System
To disarm the alarm system or turn off the
alarm if it has been activated:
.PressKon the remote key.
.Start the vehicle.
To avoid setting off the alarm by mistake:
.Lock the vehicle after all occupants have
exited.
.Always unlock a door with the
remote key.
Unlocking the driver door with the key
will not disarm the system or turn off the
alarm.
How to Detect a Tamper Condition
IfKis pressed on the remote key and the
horn chirps three times, an alarm occurred
previously while the alarm system was
armed.
If the alarm has been activated, a message
will appear on the DIC.
Steering Column Lock
If equipped, the steering column lock is a
theft-deterrent device. This feature locks the
steering column when the vehicle is turned
off and the driver door is opened, or when the driver door is opened and then the
vehicle is turned off. The steering column
unlocks when the vehicle is turned on.
The Driver Information Center (DIC) may
display one of these messages:
.A message to service the steering column
lock indicates that an issue has been
detected with the column lock feature
and the vehicle should be serviced.
.A message that the steering column is
locked indicates that the engine is
running, but the steering column is still
locked. It is normal for the column to be
locked during a remote start, but the
column should unlock after the brake
pedal is pressed and the vehicle is started.
No message will display during a remote
start.
.A message that the steering wheel must
be turned and the vehicle must be started
again indicates that the column lock
mechanism is bound, the column locking
device was unable to unlock the steering
column, and the vehicle did not start.
If this happens, immediately turn the
steering wheel from side to side to
unbind the column lock. If this does not
unlock the steering column, turn the
vehicle off and open the driver door to
reset the system. Then turn the vehicle
on and immediately turn the steering
wheel side to side for about 15 seconds.
In some cases, it may take significant
force to unbind the column.
To keep the steering column from binding,
straighten the front wheels before turning
off the vehicle.
Immobilizer
See Radio Frequency Statement 0413.
Immobilizer Operation
This vehicle has a passive theft-deterrent
system.
The system does not have to be manually
armed or disarmed.
The vehicle is automatically immobilized
when the vehicle is turned off.
The system is automatically disarmed when
the ignition is turned from off to on.