2021 GMC SIERRA Rear seat

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
274 Driving and Operating
The instrument cluster may have a Park
Assist display with bars that show“distance
to object” and object location information
for the Front and Rear Park Assist system.
As the object gets closer, more bars light up
and the bars change color from yellow to
amber to red.
When an object is first detected in the rear,
one beep will be heard from the rear,
or both sides of the Safety Alert Seat will
pulse two times. When an object is very
close —<0.4 m (1.5 ft) in the vehicle rear or
<0.3 m (1 ft) in the vehicle front —a
continuous beep will sound from the rear or
front depending on object location, or both
sides of the Safety Alert Seat will pulse five
times. Beeps for FPA are higher pitched than
for RPA.
Rear Cross Traffic Alert (RCTA)
If equipped, when the vehicle is shifted into
R (Reverse), RCTA shows a red warning
triangle with a left or right pointing arrow
on the infotainment display to warn of
traffic coming from the left or right. This
system detects objects coming from up to
20 m (65 ft) from the left or right side of
the vehicle. When an object is detected,
either three beeps sound from the left or right or three Safety Alert Seat pulses occur
on the left or right side, depending on the
direction of the detected vehicle.
Use caution while backing up when towing
a trailer, as the RCTA detection zones that
extend out from the back of the vehicle do
not move further back when a trailer is
towed.
RCTA is disabled when the trailer connection
status is displayed.
RCTA can be turned off. See
“Collision/
Detection Systems” underVehicle
Personalization 0131.
Turning the Features On or Off
PressXon the center stack to turn on or
off the Front and Rear Park Assist. The
indicator light next to the button comes on
when the features are on and turns off
when the features have been disabled. Front and Rear Park Assist can be turned
Off, On, or On with Towbar. See
“Park
Assist” underVehicle Personalization 0131.
If Park Assist is turned off through vehicle
personalization, the Park Assist button will
be disabled. To turn Park Assist on again,
select On in vehicle personalization. The On
with Towbar setting allows Park Assist to
work properly with a trailer hitch. Some
larger trailer hitches may not be compatible.
Turn off Park Assist when towing a trailer.
To turn the RPA symbols on or off, see
“Rear Camera Park Assist Symbols” under
Vehicle Personalization 0131.
Assistance Systems for Driving
If equipped, when driving the vehicle in a
forward gear, Forward Collision Alert (FCA),
Lane Departure Warning (LDW), Lane Keep
Assist (LKA), Side Blind Zone Alert (SBZA),
Lane Change Alert (LCA), Automatic
Emergency Braking (AEB), and/or the Front
Pedestrian Braking (FPB) System can help to
avoid a crash or reduce crash damage.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
276 Driving and Operating
Without Head-Up Display
When your vehicle approaches another
detected vehicle too rapidly, the red FCA
display will flash on the windshield. Also,
eight rapid high-pitched beeps will sound
from the front, or both sides of the Safety
Alert Seat will pulse five times. When this
Collision Alert occurs, the brake system may
prepare for driver braking to occur more
rapidly which can cause a brief, mild
deceleration. Continue to apply the brake
pedal as needed. Cruise control may be
disengaged when the Collision Alert occurs.
Tailgating Alert
The vehicle ahead indicator will display
amber when you are following a vehicle
ahead much too closely.
Selecting the Alert Timing
The Collision Alert control is on the steering
wheel. Press
[to set the FCA timing to
Far, Medium, or Near. The first button press
shows the current setting on the DIC.
Additional button presses will change this
setting. The chosen setting will remain until
it is changed and will affect the timing of
both the Collision Alert and the Tailgating
Alert features. The timing of both alerts will
vary based on vehicle speed. The faster the
vehicle speed, the farther away the alert will
occur. Consider traffic and weather
conditions when selecting the alert timing.
The range of selectable alert timings may
not be appropriate for all drivers and driving
conditions.
If your vehicle is equipped with Adaptive
Cruise Control (ACC), changing the FCA
timing setting automatically changes the
following gap setting (Far, Medium,
or Near).
Following Distance Indicator
The following distance to a moving vehicle
ahead in your path is indicated in following
time in seconds on the Driver Information
Center (DIC). The minimum following time is
0.5 seconds away. If there is no vehicle
detected ahead, or the vehicle ahead is out
of sensor range, dashes will be displayed.
Unnecessary Alerts
FCA may provide unnecessary alerts for
turning vehicles, vehicles in other lanes,
objects that are not vehicles, or shadows.
These alerts are normal operation and the
vehicle does not need service.
Cleaning the System
If the FCA system does not seem to operate
properly, this may correct the issue:
.Clean the outside of the windshield in
front of the rearview mirror.
.Clean the entire front of the vehicle.
.Clean the headlamps.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
282 Driving and Operating
{Warning
The LKA system does not continuously
steer the vehicle. It may not keep the
vehicle in the lane or give a Lane
Departure Warning (LDW) alert, even if a
lane marking is detected.
The LKA and LDW systems may not:
.Provide an alert or enough steering
assist to avoid a lane departure or
crash.
.Detect lane markings under poor
weather or visibility conditions. This
can occur if the windshield or
headlamps are blocked by dirt, snow,
or ice; if they are not in proper
condition; or if the sun shines directly
into the camera.
.Detect road edges.
.Detect lanes on winding or hilly roads.
If LKA only detects lane markings on one
side of the road, it will only assist or
provide an LDW alert when approaching
the lane on the side where it has
detected a lane marking. Even with LKA
and LDW, you must steer the vehicle. (Continued)
Warning (Continued)
Always keep your attention on the road
and maintain proper vehicle position
within the lane, or vehicle damage,
injury, or death could occur. Always keep
the windshield, headlamps, and camera
sensors clean and in good repair. Do not
use LKA in bad weather conditions or on
roads with unclear lane markings, such as
construction zones.
{Warning
Using LKA while towing a trailer or on
slippery roads could cause loss of control
of the vehicle and a crash. Turn the
system off.
How the System Works
LKA uses a camera sensor installed on the
windshield ahead of the rearview mirror to
detect lane markings. It may provide brief
steering assist if it detects an unintended
lane departure. It may further provide an
audible alert or the driver seat may pulse
indicating that a lane marking has been
crossed. To turn LKA on and off, press
Aon the
center stack. If equipped, the indicator light
on the button comes on when LKA is on and
turns off when LKA is disabled.
When on,
Ais white, if equipped,
indicating that the system is not ready to
assist.
Ais green if LKA is ready to
assist. LKA may assist by gently turning the
steering wheel if the vehicle approaches a
detected lane marking.
Ais amber when
assisting. It may also provide a Lane
Departure Warning (LDW) alert by flashing
Aamber if the vehicle crosses a
detected lane marking. Additionally, there
may be three beeps, or the driver seat may
pulse three times, on the right or left,
depending on the lane departure direction.
Take Steering
The LKA system does not continuously steer
the vehicle. If LKA does not detect active
driver steering, an alert and chime may be
provided. Steer the vehicle to dismiss. LKA
may become temporarily unavailable after
repeated take steering alerts.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Vehicle Care 357
Instrument Panel Fuse Block (Left)
The left instrument panel fuse block access
door is on the driver side edge of the
instrument panel.
The vehicle may not be equipped with all of
the fuses, relays, and features shown.
Pull off the cover to access the fuse block.
A fuse puller is available in the left
instrument panel end cap.
The vehicle may not be equipped with all of
the fuses, relays, and features shown.Fuses Usage
F1 Rear heated seats left/right
F3 –
F4 –
F5 Spare/MFEG
F6 Heated and ventilated seats left/right
F8 –
F9 Passive entry passive start/ Spare
F10 –
F11 –
F12 Passenger power seat
F13 Export power take off/ Special equipment option 1
F14 –
F15 –
F16 AMP F17 –
F18 –

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
366 Vehicle Care
Motor Vehicle Safety Standards. The
DOT code includes the Tire Identification
Number (TIN), an alphanumeric
designator which can also identify the
tire manufacturer, production plant,
brand, and date of production.
GVWR
:Gross Vehicle Weight Rating.
See Vehicle Load Limits 0222.
GAWR FRT
:Gross Axle Weight Rating
for the front axle. See Vehicle Load
Limits 0222.
GAWR RR
:Gross Axle Weight Rating
for the rear axle. See Vehicle Load
Limits 0222.
Intended Outboard Sidewall
:The side
of an asymmetrical tire that must
always face outward when mounted on
a vehicle.
Kilopascal (kPa)
:The metric unit for air
pressure.
Light Truck (LT-Metric) Tire
:A tire used
on light duty trucks and some
multipurpose passenger vehicles. Load Index
:An assigned number
ranging from 1 to 279 that corresponds
to the load carrying capacity of a tire.
Maximum Inflation Pressure
:The
maximum air pressure to which a cold
tire can be inflated. The maximum air
pressure is molded onto the sidewall.
Maximum Load Rating
:The load rating
for a tire at the maximum permissible
inflation pressure for that tire.
Maximum Loaded Vehicle Weight
:The
sum of curb weight, accessory weight,
vehicle capacity weight, and production
options weight.
Normal Occupant Weight
:The number
of occupants a vehicle is designed to
seat multiplied by 68 kg (150 lb). See
Vehicle Load Limits 0222.
Occupant Distribution
:Designated
seating positions.
Outward Facing Sidewall
:The side of
an asymmetrical tire that has a
particular side that faces outward when
mounted on a vehicle. The side of the
tire that contains a whitewall, bears white lettering, or bears manufacturer,
brand, and/or model name molding
that is higher or deeper than the same
moldings on the other sidewall of
the tire.
Passenger (P-Metric) Tire
:A tire used
on passenger cars and some light duty
trucks and multipurpose vehicles.
Recommended Inflation Pressure
:
Vehicle manufacturer's recommended
tire inflation pressure as shown on the
tire placard. See Tire Pressure0367 and
Vehicle Load Limits 0222.
Radial Ply Tire
:A pneumatic tire in
which the ply cords that extend to the
beads are laid at 90 degrees to the
centerline of the tread.
Rim
:A metal support for a tire and
upon which the tire beads are seated.
Sidewall
:The portion of a tire between
the tread and the bead.
Speed Rating
:An alphanumeric code
assigned to a tire indicating the
maximum speed at which a tire can
operate.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Vehicle Care 387
13. Tighten the nuts firmly in a crisscrosssequence, as shown, by turning the
wheel wrench clockwise.
When reinstalling the regular wheel and tire,
also reinstall either the center cap,
or bolt-on hub cap, depending on what the
vehicle is equipped with. For center caps,
place the cap on the wheel and tap it into
place until it seats flush with the wheel. The
cap only goes on one way. Be sure to line
up the tab on the center cap with the
indentation on the wheel. For bolt-on hub
caps, align the plastic nut caps with the
wheel nuts and then tighten by hand. Then
use the wheel wrench to tighten.
Storing a Flat or Spare Tire and Tools
{Warning
Storing a jack, a tire, or other equipment
in the passenger compartment of the
vehicle could cause injury. In a sudden
stop or collision, loose equipment could
strike someone. Store all these in the
proper place.
{Warning
Failure to follow these tire storage
instructions carefully could result in
personal injury or property damage if the
hoist cable fails or if the tire comes loose.
Make sure the tire is stored securely
before driving.
Caution
Storing an aluminum wheel with a flat
tire under your vehicle for an extended
period of time or with the valve stem
pointing up can damage the wheel.
Always stow the wheel with the valve
stem pointing down and have the wheel/
tire repaired as soon as possible.
Caution
The tire hoist can be damaged if there is
no tension on the cable when using it. To
have the necessary tension, the spare or
road tire and wheel assembly must be
installed on the tire hoist to use it.
{Warning
An improperly stored spare tire could
come loose and cause a crash. To avoid
personal injury or property damage,
always store the spare tire when the
vehicle is parked on a level surface.
Store the tire under the rear of the vehicle
in the spare tire carrier.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
388 Vehicle Care
1. Spare Tire (Valve Stem Pointed Down)
2. Tire/Wheel Retainer
3. Hoist Cable
4. Hoist Assembly
5. Hoist Shaft
6. Jack Handle Extensions
7. Wheel Wrench
8. Spare Tire Lock (If Equipped)
9. Hoist Shaft Access Hole
10. Hoist End of Extension Tool11. Spare Tire Cable (If Equipped)
1. If equipped with a spare tire cable,reinstall the cable to the spare wheel by
looping the cable around a wheel vent
window then pass the clip end of the cable through the looped end. The excess
cable wire should be on the valve stem
side of the spare tire.
2. Put the tire on the ground at the rear of the vehicle with the valve stem pointed
down, and to the rear.
3. Pull the cable and spring through the center of the wheel. Tilt the wheel
retainer plate down and through the
center wheel.
Make sure the retainer is fully seated
across the underside of the wheel.
4. Attach the wheel wrench (7) andextensions (6) together, as shown.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Vehicle Care 389
Caution
Use of an air wrench or other power
tools with the hoist mechanism is not
recommended and could damage the
system. Use only the tools supplied with
the hoist mechanism.
5. Insert the hoist end (10) through thehole (9) in the rear bumper and onto the
hoist shaft.
Do not use the chiseled end of the wheel
wrench.
6. Raise the tire part way upward. Make sure the retainer is seated in the wheel
opening.
7. If equipped with a spare tire cable, orientthe cable by rotating the spare tire so
that the cable is by the frame
attachment location.
8. Raise the tire fully against the underside of the vehicle by turning the wheel
wrench clockwise until you hear two
clicks or feel it skip twice. You cannot
overtighten the cable.9. Make sure the tire is stored securely.Push, pull, and then try to turn the tire.
If the tire moves, use the wheel wrench
to tighten the cable.