GMC SIERRA DENALI 2020 Owner's Guide

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
30 Keys, Doors, and Windows
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. SeeRemote Keyless Entry
(RKE) System Operation (Key
Access) 013 or
Remote Keyless Entry (RKE)
System Operation (Keyless Access)
0 16.
The vehicle must be in P (Park).
To open the tailgate:
. Press
xtwice 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 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.
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Keys, Doors, and Windows 31
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) 013 or
Remote Keyless Entry (RKE)
System Operation (Keyless
Access) 016. 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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
32 Keys, Doors, and Windows
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.
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 0115.
Tailgate Step
{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 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Keys, Doors, and Windows 33
.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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
34 Keys, Doors, and Windows
Preferred MethodAlternate 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).
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,
when enabled, will extend when the
door is opened. They will retract
three seconds after the door is
closed or immediately if the vehicle
starts moving.
Keep hands, children, pets, objects,
and clothing clear of the power
assist steps when in motion.
The steps will reverse direction if
there is an obstruction. If possible,
carefully remove the obstruction,
then open and close the door on the

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Keys, Doors, and Windows 35
same side to complete the motion.
If the obstruction is not cleared, the
assist steps remain extended.
Slight movement of the steps while
extended is normal.
Kick Switch
1. Place the vehicle in P (Park)and unlock the doors.
2. Kick the switch to extend the power assist step to the tire.
A Driver Information Center
(DIC) message displays.
3. Kick the switch again to return to normal operation.
Center Stack Switch
The power assist steps can be
extended to the tire by pressing
j.
When extending the steps with
j,
the kick switch is disabled. The
vehicle must be in P (Park) or
N (Neutral).
To extend the steps:
. Press
jto extend both steps.
A DIC message displays.
. Press
jagain to extend to the
tire. A DIC message displays. .
Press
jagain to return to
normal operation.
Enable/Disable
To enable or disable the power
assist steps, press and hold
jfor
four seconds. A DIC message
displays.
Cleaning
Clean the power assist steps
regularly. For an automatic car
wash, extend the steps while in
N (Neutral) using the center stack
switch. The steps will stow when
shifting into D (Drive).

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
36 Keys, Doors, and Windows
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 RKE transmitter.
. With a door open, press
Q
on 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
RKE transmitter 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 RKE
transmitter, 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
Kon the RKE
transmitter 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.
Disarming the Alarm System
To disarm the alarm system or turn
off the alarm if it has been activated:
. Press
Kon the RKE transmitter.
. Start the vehicle.
To avoid setting off the alarm by
mistake:
. Lock the vehicle after all
occupants have exited.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Keys, Doors, and Windows 37
.Always unlock a door with the
RKE transmitter.
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 RKE
transmitter 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
0 472.
Immobilizer Operation
This vehicle has a passive
theft-deterrent system.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
38 Keys, Doors, and Windows
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.
The security light, in the instrument
cluster, comes on if there is a
problem with arming or disarming
the theft-deterrent system.
The system has one or more RKE
transmitters matched to an
immobilizer control unit in your
vehicle. Only a correctly matched
RKE transmitter will start the
vehicle. If the transmitter is ever
damaged, you may not be able to
start your vehicle.
When trying to start the vehicle, the
security light may come on briefly
when the ignition is turned on. If the
engine does not start and the
security light stays on, there is a
problem with the system. Turn the
ignition off and try again.If the vehicle will not change ignition
modes (ACC/ACCESSORY, on, off),
and the RKE transmitter appears to
be undamaged, try another
transmitter. Or, you may try placing
the transmitter in the transmitter
pocket located in the center
console. See
Remote Keyless Entry
(RKE) System Operation (Key
Access) 013 or
Remote Keyless Entry (RKE)
System Operation (Keyless Access)
0 16.
If the ignition mode will not change
with the other transmitter or with the
transmitter in the transmitter pocket,
your vehicle needs service. If the
ignition does change modes, the
first transmitter may be faulty. See
your dealer who can service the
theft-deterrent system and have a
new RKE transmitter programmed to
the vehicle. It is possible for the immobilizer
system to learn new or replacement
RKE transmitters. Up to eight
transmitters can be programmed for
the vehicle. To program additional
transmitters, see "Programming
Transmitters to the Vehicle" under
Remote Keyless Entry (RKE)
System Operation (Key Access)
0
13 or
Remote Keyless Entry (RKE)
System Operation (Keyless Access)
0 16
Do not leave the transmitter or
device that disarms or deactivates
the vehicle theft system in the
vehicle.
When equipped with a key, if the
engine still does not start, and the
key appears to be undamaged, try
another ignition key. It may be
necessary to check the fuse. See
Fuses and Circuit Breakers 0370.
If the engine still does not start with
the other key, the vehicle needs

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Keys, Doors, and Windows 39
service. If the vehicle does start, the
first key may be faulty. See your
dealer. It is possible for the
immobilizer system to learn new or
replacement keys. Up to eight keys
can be programmed for the vehicle.
To program additional keys, see
Keys (Key Access)09or
Keys (Keyless Access) 012. Do not
leave the key or device that disarms
or deactivates the vehicle theft
system in the vehicle.
See your dealer to get a new key
blank cut exactly as the ignition key
that operates the system.Exterior Mirrors
Convex Mirrors
{Warning
A convex mirror can make things,
like other vehicles, look farther
away than they really are. If you
cut too sharply into the right lane,
you could hit a vehicle on the
right. Check the inside mirror or
glance over your shoulder before
changing lanes.
Standard Mirrors
The passenger side mirror is convex
shaped. A convex mirror's surface is
curved so more can be seen from
the driver seat. Trailer-Tow Mirrors
The upper portion of both the driver
and passenger mirrors is flat.
The lower portion of both the driver
and passenger mirrors is convex.
A convex mirror
’s surface is curved
so more can be seen from the driver
seat. The lower portion is adjusted
manually.
Manual Mirrors
If equipped, adjust manual mirrors
by moving the mirror up and down
or left to right to see a little of the
side of the vehicle and to have a
clear view behind the vehicle.
Using hood-mounted air deflectors
and add-on convex mirror
attachments could decrease mirror
performance.