
GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Keys, Doors, and Windows 15
Driver Side Shown, Passenger Side Similar
Pressing the lock/unlock button will cause
all doors to lock if any of the following
occur:
.It has been more than five seconds since
the first lock/unlock button press.
.Two lock/unlock button presses were
used to unlock all doors.
.Any vehicle door has been opened and all
doors are now closed.
Keyless Unlocking/Locking from the
Passenger Doors
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 a
passenger door handle will unlock all doors. Pressing the lock/unlock button will cause
all doors to lock if any of the following
occur:
.The lock/unlock button was used to
unlock all doors.
.Any vehicle door has been opened and all
doors are now closed.
Disable/Enable Keyless Unlocking of Exterior
Door Handles and Tailgate
If equipped, keyless unlocking of the exterior
door handles and tailgate can be disabled
and enabled.
Disabling Keyless Unlocking:
With the vehicle off, press and hold
Qand
Kon the RKE transmitter at the same time
for approximately three seconds. The turn
signal lamps will flash four times quickly to
indicate access is disabled. Using any
exterior handle to unlock the doors or open
the tailgate will cause the turn signal lamps
to flash four times quickly, indicating access
is disabled. If disabled, disarm the alarm
system before starting the vehicle. Enabling Keyless Unlocking:
With the vehicle off, press and hold
Qand
Kon the RKE transmitter at the same time
for approximately three seconds. The turn
signal lamps will flash twice quickly to
indicate access is enabled.
Passive Locking
This feature will lock the vehicle several
seconds after all doors are closed, if the
vehicle is off and at least one RKE
transmitter has been removed from the
interior, or none remain in the interior.
If other electronic devices interfere with the
RKE transmitter signal, the vehicle may not
detect the RKE transmitter inside the vehicle.
If passive locking is enabled, the doors may
lock with the RKE transmitter inside the
vehicle. Do not leave the RKE transmitter in
an unattended vehicle.
To customize the doors to automatically lock
when exiting the vehicle, see “Remote Lock,
Unlock, Start” underVehicle Personalization
0 131.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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20 Keys, Doors, and Windows
Remote Vehicle Start
If equipped with the remote start feature,
the climate control system will come on
when the vehicle is started remotely,
depending on the outside temperature.
The rear defog and heated and ventilated
seats, if equipped, may also come on. See
Heated and Ventilated Front Seats052 and
Vehicle Personalization 0131.
If equipped, the automatic heated steering
wheel may also come on. See Heated
Steering Wheel 0100.
Laws in some communities may restrict the
use of remote starters. Check local
regulations for any requirements on remote
starting of vehicles.
Do not use remote start if the vehicle is low
on fuel. The vehicle may run out of fuel.
The vehicle cannot be remote started if:
.The RKE transmitter is inside the vehicle
or if the key is in the ignition.
.The hood is not closed.
.There is an emission control system
malfunction and the lamp is on.
.The ignition is in any mode other
than off.
.The hazard warning flashers are on.
.Two remote starts or a remote start with
an extension have been used.
.The vehicle is not in P (Park).
The engine will turn off during a remote
vehicle start if:
.The coolant temperature gets too high.
.The oil pressure gets low.
The RKE transmitter range may be reduced
while the vehicle is running.
Other conditions can affect the performance
of the transmitter. See Remote Keyless Entry
(RKE) System 010.
Starting the Engine Using Remote Start
1. Press and release
Q.
2. Immediately press and hold
/until the
turn signal lamps flash or for at least
four seconds.
When the vehicle starts, the parking
lamps will turn on. The doors will be
locked and the climate control system
may come on. The engine will continue to run for
15 minutes. After 30 seconds, repeat
Steps 1 and 2 for a 15-minute time
extension.
Turn the ignition on to operate the vehicle.
Extending Engine Run Time
The engine run time can be extended by
15 minutes, for a total of 30 minutes,
if during the first 15 minutes Steps 1 and 2
are repeated while the engine is still
running. An extension can be requested
30 seconds after starting.
A maximum of two remote starts, or a
single start with an extension, is allowed
between ignition cycles.
The vehicle's ignition must be turned on and
then back off to use remote start again.
Canceling a Remote Start
To cancel a remote start, do one of the
following:
.Press and hold/until the parking lamps
turn off.
.Turn on the hazard warning flashers.
.Turn the ignition on and then off.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Keys, Doors, and Windows 21
Door Locks
{Warning
Unlocked doors can be dangerous.
.Passengers, especially children, can
easily open the doors and fall out of a
moving vehicle. The doors can be
unlocked and opened while the vehicle
is moving. The chance of being thrown
out of the vehicle in a crash is
increased if the doors are not locked.
So, all passengers should wear seat
belts properly and the doors should be
locked whenever the vehicle is driven.
.Young children who get into unlocked
vehicles may be unable to get out.
A child can be overcome by extreme
heat and can suffer permanent injuries
or even death from heat stroke.
Always lock the vehicle whenever
leaving it.
.Outsiders can easily enter through an
unlocked door when you slow down
or stop the vehicle. Locking the doors
can help prevent this from happening.There are several ways to lock and unlock
the vehicle.
From outside:
.Use the Remote Keyless Entry (RKE)
transmitter.
.Use Keyless Access, if equipped.
.Use the key in the driver door or the
passenger door, if equipped.
From inside, use the power door locks or the
manual door locks. To lock the door with
the manual door locks, push down on the
manual lock knob.
From inside, pull the door handle once to
unlock the door. Pull the handle again to
open the door.
See Vehicle Alarm System 031. Keyless Access
If equipped, the remote key must be within
1 m (3 ft) of the tailgate or door being
opened or locked. Press the button on the
door handle to open. See
“Keyless Access
Operation” inRemote Keyless Entry (RKE)
System Operation (Key Access) 010 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 013.
Free-Turning Locks
The door key lock cylinder turns freely when
either the wrong key is used, or the correct
key is not fully inserted. The free-turning
door lock feature prevents the lock from
being forced open. To reset the lock, turn it
to the vertical position with the correct key

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
22 Keys, Doors, and Windows
fully inserted. Remove the key and insert it
again. If this does not reset the lock, turn
the key halfway around in the cylinder and
repeat the reset procedure.
Power Door Locks
If equipped with power door locks.
Q:Press to lock the doors.
K:Press to unlock the doors.
Delayed Locking
If equipped, this feature delays the locking
of the doors until five seconds after all
doors are closed. Delayed locking can only be turned on when
the Open Door Anti-Lockout feature has
been turned off.
When
Qis pressed on the power door lock
switch while the door is open, a chime will
sound three times indicating delayed locking
is active.
The doors will lock automatically
five seconds after all doors are closed. If a
door is reopened before that time, the
five-second timer will reset when all doors
are closed again.
Press
Qon the door lock switch again or
press
Qon the RKE transmitter to lock the
doors immediately.
This feature can be programmed. See Vehicle
Personalization 0131.
Automatic Door Locks
If equipped, the doors will lock
automatically when all doors are closed, the
ignition is on, and the vehicle is shifted out
of P (Park). If a vehicle door is unlocked, and then
opened and closed, the doors will lock either
when your foot is removed from the brake
or the vehicle speed becomes faster than
13 km/h (8 mph).
To unlock the doors:
.PressKon the power door lock switch.
.Shift the transmission into P (Park).
Automatic door locking cannot be disabled.
Automatic door unlocking can be
programmed. See Vehicle Personalization
0 131.
Lockout Protection
If equipped, the ignition is on or in ACC/
ACCESSORY and the power door lock switch
is pressed with the driver door open, all the
doors will lock and only the driver door will
unlock.
If the vehicle is off and locking is requested
while a door is open, when all doors are
closed the vehicle will check to the Keyless
Access function (if equipped). If an RKE
transmitter is detected and the number of
RKE transmitters inside has not reduced, the
driver door will unlock and the horn will
chirp three times.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Keys, Doors, and Windows 23
Lockout Protection can be manually
overridden with the driver door open by
pressing and holding
Qon the power door
lock switch.
Open Door Anti-Lockout
If equipped, the Open Door Anti-Lockout is
turned on and the vehicle is off, the driver
door is open, and locking is requested, all
the doors will lock and the driver door will
unlock. The Open Door Anti-Lockout feature
can be turned on or off. See Vehicle
Personalization 0131.
Safety Locks
The rear door safety locks prevent
passengers from opening the rear doors
from inside the vehicle.
The safety lock is on the inside edge of the
rear doors. To use the safety lock:
1. Move the lever down to the lock position.
2. Close the door.
3. Do the same for the other rear door.
To open a rear door when the safety lock
is on: 1. Unlock the door by activating the inside handle, by pressing the power door
unlock switch, or by using the Remote
Keyless Entry (RKE) transmitter.
2. Open the door from the outside. When the safety lock is enabled, adults and
older children will not be able to open the
rear door from the inside. Cancel the safety
locks to enable the doors to open from the
inside.
To cancel the safety lock:
1. Unlock the door and open it from the outside.
2. Move the lever up to unlock. Do the same for the other door.Doors
Tailgate
Manual Tailgate
{Warning
It is extremely dangerous to ride on the
tailgate, even when the vehicle is
operated at low speeds. People riding on
the tailgate can easily lose their balance
and fall in response to vehicle maneuvers.
Falling from a moving vehicle may result
in serious injuries or death. Do not allow
people to ride on the tailgate. Be sure
everyone in your vehicle is in a seat and
using a seat belt properly.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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24 Keys, Doors, and Windows
Use the key to unlock the tailgate.
Open the tailgate by lifting up on its handle
while pulling the tailgate down.
To shut the tailgate, firmly push it upward
until it latches.
After closing the tailgate, pull it back to be
sure it is latched securely.
Some tailgates have an electric latch. If the
battery is disconnected or has low voltage,
the tailgate will not open. The tailgate will
resume operation when the battery is
reconnected or recharged.
Power Release 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.
In the case of a dead battery, the tailgate
can be opened manually. Contact your
dealer or Roadside Assistance.
If equipped, to lock or unlock the tailgate,
use the RKE transmitter or the key. See
Remote Keyless Entry (RKE) System
Operation (Key Access) 010 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 013.
The vehicle must be in P (Park).
To open the tailgate:
.Pressxtwice quickly on the RKE
transmitter until the tailgate moves.
.Press5on the center stack.
.Press the touch pad on the tailgate
handle after unlocking all doors. Use the
top of the tailgate to pull against if

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Keys, Doors, and Windows 25
assistance is required. If equipped with
Keyless Access, a locked tailgate can be
opened if the RKE transmitter is within
1 m (3 ft).
To close the tailgate, firmly push it upward
until it latches. Pull it back to be sure it is
latched securely.
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 RKE
transmitter until the tailgate moves. See
Remote Keyless Entry (RKE) System
Operation (Key Access) 010 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 013.
If equipped with Keyless Access, a locked
tailgate can be opened if the RKE
transmitter 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 RKE transmitter once,
then quickly press and hold
xuntil the
tailgate completely closes. If
xis
released prior to it being fully closed, the
tailgate will reopen.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Keys, Doors, and Windows 27
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).
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 RKE
transmitter until the tailgate moves. See
Remote Keyless Entry (RKE) System
Operation (Key Access) 010 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 013.
If equipped with Keyless Access, the
tailgate can be opened if the RKE
transmitter 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.