GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
12 Keys, Doors, and Windows
With an active OnStar or connected service
plan, an OnStar Advisor may remotely
unlock the vehicle. SeeOnStar Overview
0 408.
If locked out of the vehicle, see Roadside
Assistance Program 0399.
If equipped with memory seats, RKE
transmitters 1 and 2 are linked to seating
positions of memory 1 or 2. See Memory
Seats 053.
Remote Keyless Entry (RKE)
System
See Radio Frequency Statement 0404.
If there is a decrease in the Remote Keyless
Entry (RKE) operating range:
.Check the distance. The transmitter may
be too far from the vehicle.
.Check the location. Other vehicles or
objects may be blocking the signal.
.Check the transmitter's battery. See
“Battery Replacement” later in this
section.
.If the transmitter is still not working
correctly, see your dealer or a qualified
technician for service.
Remote Keyless Entry (RKE)
System Operation (Key Access)
The RKE transmitter functions may work up
to 60 m (197 ft) away from the vehicle.
Other conditions can affect the performance
of the transmitter. See Remote Keyless Entry
(RKE) System 012.
/:Press and releaseQ, then immediately
press and hold
/until the turn signal
lamps flash or for at least four seconds. The
engine may be started from outside the
vehicle using the RKE transmitter. See
Remote Vehicle Start 022.
Q:Press to lock all doors. If enabled, the turn signal lamps may flash
and/or the horn may sound on the second
press to indicate locking has occurred.
If enabled, the horn chirps when
Qis
pressed again within three seconds. To view
available settings from the infotainment
screen, touch Settings > Vehicle > Remote
Lock, Unlock, Start.
Pressing
Qarms the alarm system. See
Vehicle Alarm System 034.
If equipped with remote mirror folding,
pressing and holding
Qfor one second will
fold the mirrors, if enabled. To view
available settings for this feature, touch the
Settings icon on the infotainment home
page. Select “Vehicle”to display the list of
available options and select “Comfort and
Convenience”.
K: Press once to unlock only the driver
door. If
Kis pressed again within
three seconds, all remaining doors unlock.
The interior lamps may come on and stay
on for 20 seconds or until the ignition is
turned on.
If enabled, the turn signal lamps flash twice
to indicate unlocking has occurred.
If enabled, the exterior lamps may turn on.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
16 Keys, Doors, and Windows
tailgate unlock. The interior lamps may
come on and stay on for 20 seconds or until
the ignition is turned on.
If enabled, the turn signal lamps flash twice
to indicate unlocking has occurred.
If enabled, the exterior lamps may turn on.
To view available settings for this feature,
touch the Settings icon on the infotainment
home page. Select“Vehicle”to display the
list of available options and select “Remote
Lock, Unlock, Start”.
Pressing
Kon the RKE transmitter disarms
the alarm system. See Vehicle Alarm System
0 34.
If equipped with remote mirror folding,
pressing and holding
Kfor one second will
unfold the mirrors, if enabled. To view
available settings for this feature, touch the
Settings icon on the infotainment home
page. Select “Vehicle”to display the list of
available options and select “Comfort and
Convenience”.
Press and hold
Kuntil the windows fully
open, if remote window operation is
enabled. To view available settings for this
feature, touch the Settings icon on the infotainment home page. Select
“Vehicle”to
display the list of available options and
select “Remote Lock, Unlock, Start”.
x:Press twice quickly to release the
tailgate, if equipped.
7: Press and release to initiate vehicle
locator. The turn signal lamps flash and the
horn sounds three times.
Press and hold
7for more than
three seconds to activate the panic alarm.
The turn signal lamps flash and the horn
sounds repeatedly for 30 seconds. The alarm
turns off when the ignition is turned on or
7is pressed again. The ignition must be off
for the panic alarm to work.
Keyless Access Operation
The Keyless Access system allows for doors
and the tailgate to be accessed without
pressing the RKE transmitter button. The RKE
transmitter must be within 1 m (3 ft) of the
tailgate or door being opened. If the vehicle
has this feature, there will be a button on
the outside door handles. Keyless Access can be programmed to
unlock all doors on the first lock/unlock
press from the driver door. Keyless
Unlocking can also be turned off. To view
available settings for this feature, touch the
Settings icon on the infotainment home
page. Select
“Vehicle”to display the list of
available options and select “Remote Lock,
Unlock, Start”.
If equipped with memory seats, RKE
transmitters 1 and 2 are linked to seating
positions of memory 1 or 2. See Memory
Seats 053.
Keyless Unlocking/Locking from the
Driver Door
When the doors are locked and the RKE
transmitter is within 1 m (3 ft) of the door
handle, pressing the lock/unlock button on
the driver door handle will unlock the driver
door. If the lock/unlock button is pressed
again within five seconds, all passenger
doors and the tailgate will unlock.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
50 Seats and Restraints
Adjust the head restraint so that the top of
the restraint is at the same height as the
top of the occupant's head. This position
reduces the chance of a neck injury in a
crash.
To raise or lower the head restraint, press
the button on the side of the head restraint
and pull up or push the head restraint down
and release the button.
Pull and push on the head restraint after the
button is released to make sure that it is
locked in place.
The front seat outboard head restraints are
not removable.
Rear Head Restraints
The vehicle’s rear seat has head restraints in
the outboard seating positions that cannot
be adjusted.
The head restraint can be folded forward to
allow for better visibility when the rear seat
is unoccupied. To fold the head restraint,
press the button on the side of the head
restraint.
When an occupant is in the seat, always
return the head restraint to the upright
position until it locks into place. Push and
pull on the head restraint to make sure that
it is locked.If you are installing a child restraint in the
rear seat, see
Lower Anchors and Tethers for
Children (LATCH System) 082.
Center Headrest
The vehicle’s rear seat may be equipped
with a headrest in the center seating
position that cannot be adjusted.
If you are installing a child restraint in the
rear seat, see Lower Anchors and Tethers for
Children (LATCH System) 082.
Front Seats
Seat Adjustment
{Warning
You can lose control of the vehicle if you
try to adjust a driver seat while the
vehicle is moving. Adjust the driver seat
only when the vehicle is not moving.
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Seats and Restraints 51
To adjust a manual seat:1. Pull the handle at the front of the seat.
2. Slide the seat to the desired position and release the handle.
3. Try to move the seat back and forth to be sure it is locked in place.
To adjust the seatback, see Reclining
Seatbacks 052.
To adjust the lumbar support, if equipped,
see Lumbar Adjustment 053.
Center Seat
If equipped, the center front seatback
doubles as an armrest and cupholder/
storage area for the driver and passenger
when the center front seat is not used.
Pull the strap on the side of the center
seatback to fold the center seatback. Do not
use the center seatback as a seating position
when the seatback is folded down.
To raise the seatback, push the seatback
rearward until it locks in the upright
position. Push and pull on the seatback to
make sure it is locked.
Power Seat Adjustment
To adjust a power seat, if equipped:
.Move the seat forward or rearward by
sliding the control forward or rearward.
.Raise or lower the front part of the seat
cushion by moving the front of the
control up or down.
.Raise or lower the seat by moving the
rear of the control up or down.
To adjust the seatback, see Reclining
Seatbacks 052.
To adjust the lumbar support, see Lumbar
Adjustment 053.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
52 Seats and Restraints
Some vehicles are equipped with a feature
that activates a vibrating pulse alert in the
driver seat to help the driver avoid crashes.
SeeDriver Assistance Systems 0246.
Reclining Seatbacks
{Warning
Sitting in a reclined position when the
vehicle is in motion can be dangerous.
Even when buckled up, the seat belts
cannot do their job.
The shoulder belt will not be against
your body. Instead, it will be in front of
you. In a crash, you could go into it,
receiving neck or other injuries.
The lap belt could go up over your
abdomen. The belt forces would be there,
not at your pelvic bones. This could cause
serious internal injuries.
For proper protection when the vehicle is
in motion, have the seatback upright.
Then sit well back in the seat and wear
the seat belt properly.
Do not have a seatback reclined if the
vehicle is moving.
Manual Reclining Seatbacks
{Warning
If either seatback is not locked, it could
move forward in a sudden stop or crash.
That could cause injury to the person
sitting there. Always push and pull on
the seatbacks to be sure they are locked.
To adjust a manual seatback:
1. Lift the lever. The seatback will automatically fold
forward.
2. To recline, move the seatback rearward to the desired position, then release the
lever to lock the seatback in place.
3. Push and pull on the seatback to make sure it is locked.
To return the seatback to the upright
position: 1. Lift the lever fully without applying pressure to the seatback, and the
seatback will return to the upright
position.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Seats and Restraints 57
To enable or disable remote start heated or
ventilated seats, select Settings > Vehicle >
Remote Lock, Unlock, and Start > Remote
Start Auto Heat Seats or Remote Start Auto
Cool Seats > ON or OFF. SeeRemote Vehicle
Start 022.
Rear Seats
Rear Seat Reminder
If equipped, the message REAR SEAT
REMINDER LOOK IN REAR SEAT displays
under certain conditions indicating there
may be an item or passenger in the rear
seat. Check before exiting the vehicle.
This feature will activate when a second row
door is opened while the vehicle is on or up
to 10 minutes before the vehicle is turned
on. There will be an alert when the vehicle
is turned off. The alert does not directly
detect objects in the rear seat; instead,
under certain conditions, it detects when a
rear door is opened and closed, indicating
that there may be something in the
rear seat. The feature is active only once each time
the vehicle is turned on and off, and will
require reactivation by opening and closing
the second row doors. There may be an
alert even when there is nothing in the rear
seat; for example, if a child entered the
vehicle through the rear door and left the
vehicle without the vehicle being shut off.
The feature can be turned on or off. Select
Settings > Vehicle > Rear Seat Reminder >
ON or OFF.
Folding the Rear Seat Cushion
Either side of the rear seat cushion can be
folded up for added cargo space.
Caution
Folding a rear seat with the seat belts
still fastened may cause damage to the
seat or the seat belts. Always unbuckle
the seat belts and return them to their
normal stowed position before folding a
rear seat.
Make sure that nothing is on the seat
cushion.
To fold the seat, slowly pull the seat
cushion up.
To return the seat to the normal seating
position, slowly pull the seat cushion down.
{Warning
A seat belt that is improperly routed, not
properly attached, or twisted will not
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 seat belts are properly routed and
attached, and are not twisted.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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Seats and Restraints 61
Never route the lap or shoulder belt over an
armrest.
{Warning
The seat belt can be pinched if it is
routed under plastic trim on the seat,
such as trim around the rear seatback
folding handle or side airbag. In a crash,
pinched seat belts might not provide
adequate protection. Never allow seat
belts to be routed under plastic trim
pieces.
{Warning
You can be seriously injured or killed if
the shoulder belt is worn behind your
back, under your legs, or wrapped around
your neck. The shoulder belt can tighten
but cannot be loosened if it is locked. The
shoulder belt locks when it is pulled all
the way out of the retractor. It unlocks
when the shoulder belt is allowed to go
all the way back into the retractor, but it
cannot do this if it is wrapped around
you. You may have to cut the seat belt if
it is locked and tightened around you.
Lap-Shoulder Belt
All seating positions in the vehicle have a
lap-shoulder belt.
The following instructions explain how to
wear a lap-shoulder belt properly.1. Adjust the seat, if the seat is adjustable, so you can sit up straight. To see how,
see “Seats” in the Index.
2. Pick up the latch plate and pull the belt
across you. Do not let it get twisted.
The lap-shoulder belt may lock if you
pull the belt across you very quickly.
If this happens, let the belt go back
slightly to unlock it. Then pull the belt
across you more slowly.
If the shoulder portion of a passenger
belt is pulled out all the way, the child
restraint locking feature may be
engaged. See Child Restraint Systems
0 79. If this occurs, let the belt go back
all the way and start again. If the
locking feature stays engaged after
letting the belt go back to stowed
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Seats and Restraints 87
According to accident statistics, children and
infants are safer when properly restrained in
a child restraint system or infant restraint
system secured in a rear seating position.
SeeWhere to Put the Restraint 080 for
additional information.
Securing a Child Restraint Designed for
the LATCH System
{Warning
A child could be seriously injured or killed
in a crash if the child restraint is not
properly attached to the vehicle using
either the LATCH anchors or the vehicle
seat belt. Follow the instructions that
came with the child restraint and the
instructions in this manual.
{Warning
Do not attach more than one child
restraint to a single anchor, except for
the center top tether anchors in the crew
cab models. Attaching more than one
child restraint to a single anchor could
cause the anchor or attachment to come
loose or even break during a crash.
(Continued)
Warning (Continued)
A child or others could be injured. To
reduce the risk of serious or fatal injuries
during a crash, attach only one child
restraint per anchor.
{Warning
Children can be seriously injured or
strangled if a shoulder belt is wrapped
around their neck. The shoulder belt can
tighten but cannot be loosened if it is
locked. The shoulder belt locks when it is
pulled all the way out of the retractor.
It unlocks when the shoulder belt is
allowed to go all the way back into the
retractor, but it cannot do this if it is
wrapped around a child’s neck. If the
shoulder belt is locked and tightened
around a child’s neck, the only way to
loosen the belt is to cut it.
Buckle any unused seat belts behind the
child restraint so children cannot reach
them. Pull the shoulder belt all the way
out of the retractor to set the lock, and(Continued)
Warning (Continued)
tighten the belt behind the child restraint
after the child restraint has been
installed.
Caution
Do not let the LATCH attachments rub
against the vehicle’s seat belts. This may
damage these parts. If necessary, move
buckled seat belts to avoid rubbing the
LATCH attachments.
Do not fold the rear seat cushion when
the seat is occupied. Do not fold the
empty rear seat with a seat belt buckled.
This could damage the seat belt or the
seat. Unbuckle and return the seat belt to
its stowed position, before folding
the seat.
If you need to secure more than one child
restraint in the rear seat, see Where to Put
the Restraint 080.