service GMC SIERRA DENALI 2020 User Guide
[x] Cancel search | Manufacturer: GMC, Model Year: 2020, Model line: SIERRA DENALI, Model: GMC SIERRA DENALI 2020Pages: 501, PDF Size: 7.61 MB
Page 80 of 501

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Seats and Restraints 79
Warning (Continued)
secure child restraints in the rear
seat. Consider using another
vehicle to transport the child
when a rear seat is not available.
If the vehicle does not have a rear
seat that will accommodate a
rear-facing child restraint, a
rear-facing child restraint should not
be installed in the vehicle, even if
the airbag is off.
The passenger sensing system is
designed to turn off the front
outboard passenger frontal airbag if:
. The front outboard passenger
seat is unoccupied.
. The system determines an infant
is present in a child restraint.
. A front outboard passenger
takes his/her weight off of the
seat for a period of time.
. There is a critical problem with
the airbag system or the
passenger sensing system. When the passenger sensing
system has turned off the front
outboard passenger frontal airbag,
the OFF indicator will light and stay
lit as a reminder that the airbag is
off. See
Passenger Airbag Status
Indicator 0136.
The passenger sensing system is
designed to turn on the front
outboard passenger frontal airbag
anytime the system senses that a
person of adult size is sitting
properly in the front outboard
passenger seat.
When the passenger sensing
system has allowed the airbag to be
enabled, the ON indicator will light
and stay lit as a reminder that the
airbag is active.
For some children, including
children in child restraints, and for
very small adults, the passenger
sensing system may or may not turn
off the front outboard passenger
frontal airbag, depending upon the
person's seating posture and body
build. Everyone in the vehicle who
has outgrown child restraints should wear a seat belt properly
—whether
or not there is an airbag for that
person.
{Warning
If the airbag readiness light ever
comes on and stays on, it means
that something may be wrong
with the airbag system. To help
avoid injury to yourself or others,
have the vehicle serviced right
away. See Airbag Readiness
Light 0135 for more information,
including important safety
information.
If the On Indicator Is Lit for a
Child Restraint
The passenger sensing system is
designed to turn off the front
outboard passenger frontal airbag if
the system determines that an infant
is present in a child restraint. If a
child restraint has been installed
and the ON indicator is lit:
1. Turn the vehicle off.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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82 Seats and Restraints
Warning (Continued)
seatback may interfere with the
proper operation of the passenger
sensing system.
Servicing the
Airbag-Equipped Vehicle
Airbags affect how the vehicle
should be serviced. There are parts
of the airbag system in several
places around the vehicle. Your
dealer and the service manual have
information about servicing the
vehicle and the airbag system. To
purchase a service manual, see
Publication Ordering Information
0471.
{Warning
For up to 10 seconds after the
vehicle is turned off and the
battery is disconnected, an airbag
can still inflate during improper
service. You can be injured if you
(Continued)
Warning (Continued)
are close to an airbag when it
inflates. Avoid yellow connectors.
They are probably part of the
airbag system. Be sure to follow
proper service procedures, and
make sure the person performing
work for you is qualified to do so.
Adding Equipment to the
Airbag-Equipped Vehicle
Adding accessories that change the
vehicle's frame, bumper system,
height, front end, or side sheet
metal, may keep the airbag system
from working properly.
The operation of the airbag system
can also be affected by changing,
including improperly repairing or
replacing, any parts of the following:
.Airbag system, including airbag
modules, front or side impact
sensors, sensing and diagnostic
module, or airbag wiring .
Front seats, including stitching,
seams, or zippers
. Seat belts
. Steering wheel, instrument
panel, overhead console, ceiling
trim, or pillar garnish trim
. Inner door seals, including
speakers
Your dealer and the service manual
have information about the location
of the airbag modules and sensors,
sensing and diagnostic module, and
airbag wiring along with the proper
replacement procedures.
In addition, the vehicle has a
passenger sensing system for the
front outboard passenger position,
which includes sensors that are part
of the passenger seat. The
passenger sensing system may not
operate properly if the original seat
trim is replaced with non-GM
covers, upholstery, or trim; or with
GM covers, upholstery, or trim
designed for a different vehicle. Any
object, such as an aftermarket seat
heater or a comfort-enhancing pad
or device, installed under or on top
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Seats and Restraints 83
of the seat fabric, could also
interfere with the operation of the
passenger sensing system. This
could either prevent proper
deployment of the passenger
airbag(s) or prevent the passenger
sensing system from properly
turning off the passenger airbag(s).
SeePassenger Sensing System
0 77.
If the vehicle has rollover roof-rail
airbags, see Different Size Tires
and Wheels 0401 for additional
important information.
If a snow plow is added to the
vehicle, the airbags should still work
properly. The airbag systems were
designed to work properly under a
wide range of conditions, including
snow plowing with vehicles that
have the optional snow plow prep
package (RPO VYU). Do not
change or defeat the snow plow's
“tripping mechanism.” If you do, it
can damage the snow plow and the
vehicle, and may cause an airbag
deployment. If the vehicle must be modified
because you have a disability and
have questions about whether the
modifications will affect the vehicle's
airbag system, or if you have
questions about whether the airbag
system will be affected if the vehicle
is modified for any other reason, call
Customer Assistance. See
Customer Assistance Offices
0464.
Airbag System Check
The airbag system does not need
regularly scheduled maintenance or
replacement. Make sure the airbag
readiness light is working. See
Airbag Readiness Light 0135.
Caution
If an airbag covering is damaged,
opened, or broken, the airbag
may not work properly. Do not
open or break the airbag
coverings. If there are any
opened or broken airbag
coverings, have the airbag
(Continued)
Caution (Continued)
covering and/or airbag module
replaced. For the location of the
airbags, seeWhere Are the
Airbags? 073. See your dealer
for service.
Replacing Airbag System
Parts after a Crash
{Warning
A crash can damage the airbag
systems in the vehicle.
A damaged airbag system may
not properly protect you and your
passenger(s) in a crash, resulting
in serious injury or even death. To
help make sure the airbag
systems are working properly
after a crash, have them
inspected and any necessary
replacements made as soon as
possible.
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84 Seats and Restraints
If an airbag inflates, you will need to
replace airbag system parts. See
your dealer for service.
If the airbag readiness light stays on
after the vehicle is started or comes
on when you are driving, the airbag
system may not work properly. Have
the vehicle serviced right away. See
Airbag Readiness Light0135.Child Restraints
Older Children
Older children who have outgrown
booster seats should wear the
vehicle’s seat belts.
The manufacturer instructions that
come with the booster seat state the
weight and height limitations for that
booster. Use a booster seat with a
lap-shoulder belt until the child
passes the fit test below: .
Sit all the way back on the seat.
Do the knees bend at the seat
edge? If yes, continue. If no,
return to the booster seat.
. Buckle the lap-shoulder belt.
Does the shoulder belt rest on
the shoulder? If yes, continue.
If no, try using the rear seat belt
comfort guide, if available. See
“Rear Seat Belt Comfort Guides”
under Lap-Shoulder Belt 067.
If a comfort guide is not
available, or if the shoulder belt
still does not rest on the
shoulder, then return to the
booster seat.
. Does the lap belt fit low and
snug on the hips, touching the
thighs? If yes, continue. If no,
return to the booster seat.
. Can proper seat belt fit be
maintained for the length of the
trip? If yes, continue. If no,
return to the booster seat.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Instruments and Controls 117
Instruments and
Controls
Controls
Steering Wheel Adjustment . . . 118
Steering Wheel Controls . . . . . . 119
Heated Steering Wheel . . . . . . . 119
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Windshield Wiper/Washer . . . . 119
Compass . . . . . . . . . . . . . . . . . . . . . 120
Clock . . . . . . . . . . . . . . . . . . . . . . . . . 120
Power Outlets . . . . . . . . . . . . . . . . 121
Wireless Charging . . . . . . . . . . . . 122
Warning Lights, Gauges, and
Indicators
Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . 125
Instrument Cluster . . . . . . . . . . . . 126
Speedometer . . . . . . . . . . . . . . . . . 130
Odometer . . . . . . . . . . . . . . . . . . . . . 131
Trip Odometer . . . . . . . . . . . . . . . . 131
Tachometer . . . . . . . . . . . . . . . . . . . 131
Fuel Gauge . . . . . . . . . . . . . . . . . . . 131
Engine Oil Pressure Gauge . . . . . . . . . . . . . . . . . . . . . . 132
Engine Coolant Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . 133 Voltmeter Gauge . . . . . . . . . . . . . 134
Seat Belt Reminders . . . . . . . . . 135
Airbag Readiness Light . . . . . . . 135
Passenger Airbag Status
Indicator . . . . . . . . . . . . . . . . . . . . 136
Charging System Light . . . . . . . 137
Malfunction Indicator Lamp (Check Engine Light) . . . . . . . . 137
Brake System Warning Light . . . . . . . . . . . . . . . . . . . . . . . . 139
Electric Parking Brake Light . . . . . . . . . . . . . . . . . . . . . . . . 140
Service Electric Parking Brake Light . . . . . . . . . . . . . . . . . . . . . . . . 140
Antilock Brake System (ABS) Warning Light . . . . . . . . . . . . . . . 140
Four-Wheel-Drive Light . . . . . . . 141
Tow/Haul Mode Light . . . . . . . . . 141
Hill Descent Control Light . . . . 141
Lane Departure Warning (LDW) Light (2500/3500
Series) . . . . . . . . . . . . . . . . . . . . . . 141
Lane Keep Assist (LKA) Light (1500 Series) . . . . . . . . . . . . . . . 142
Vehicle Ahead Indicator . . . . . . 142
Pedestrian Ahead Indicator . . . 142
Traction Off Light . . . . . . . . . . . . . 142
Traction Control System (TCS)/ Electronic Stability Control
Light . . . . . . . . . . . . . . . . . . . . . . . . 143 Electronic Stability Control
(ESC) Off Light . . . . . . . . . . . . . . 143
Engine Coolant Temperature Warning Light . . . . . . . . . . . . . . . 144
Driver Mode Control Light . . . . 144
Tire Pressure Light . . . . . . . . . . . 144
Engine Oil Pressure Light
(Uplevel Cluster) . . . . . . . . . . . . 145
Low Fuel Warning Light . . . . . . 145
Security Light . . . . . . . . . . . . . . . . . 146
High-Beam On Light . . . . . . . . . . 146
Front Fog Lamp Light . . . . . . . . . 146
Lamps On Reminder . . . . . . . . . 146
Cruise Control Light . . . . . . . . . . 146
Door Ajar Light . . . . . . . . . . . . . . . 147
Information Displays
Driver Information Center (DIC) (Base Level) . . . . . . . . . . . . . . . . 147
Driver Information Center (DIC) (Midlevel and Uplevel) . . . . . . 148
Head-Up Display (HUD) . . . . . . 152
Vehicle Messages
Vehicle Messages . . . . . . . . . . . . 155
Engine Power Messages . . . . . 155
Vehicle Speed Messages . . . . . 156
Vehicle Personalization
Vehicle Personalization . . . . . . . 156
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THIS SOFTWARE IS PROVIDED
BY THE COPYRIGHT HOLDERS
AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, BUT
NOT LIMITED TO, THE IMPLIED
WARRANTIES OF
MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT
SHALL THE COPYRIGHT HOLDER
OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL,
EXEMPLARY, OR
CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED
TO, PROCUREMENT OF
SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA,OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY
OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF
THE USE OF THIS SOFTWARE,
EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.Warning Lights,
Gauges, and
Indicators
Warning lights and gauges can
signal that something is wrong
before it becomes serious enough
to cause an expensive repair or
replacement. Paying attention to the
warning lights and gauges could
prevent injury.
Some warning lights come on briefly
when the engine is started to
indicate they are working. When
one of the warning lights comes on
and stays on while driving, or when
one of the gauges shows there may
be a problem, check the section that
explains what to do. Waiting to do
repairs can be costly and even
dangerous.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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132 Instruments and Controls
Midlevel English Fuel Gauge
Shown, Base Level and Uplevel Fuel Gauge Similar
When the ignition is on, the fuel
gauge indicates about how much
fuel is left in the tank.
There is an arrow near the fuel
gauge pointing to the side of the
vehicle the fuel door is on.
When the indicator nears empty, the
low fuel light comes on. There still is
a little fuel left, but the vehicle
should be refueled soon. Here are four things that some
owners ask about. None of these
show a problem with the fuel gauge:
.
At the service station, the fuel
pump shuts off before the gauge
reads full.
. It takes a little more or less fuel
to fill up than the gauge
indicated. For example, the
gauge may have indicated the
tank was half full, but it actually
took a little more or less than
half the tank's capacity to fill
the tank.
. The gauge moves a little while
turning a corner or speeding up.
. The gauge takes a few seconds
to stabilize after the ignition is
turned on, and goes back to
empty when the ignition is
turned off.
Engine Oil Pressure
Gauge
Midlevel Metric Shown, Base Level
and Uplevel Similar
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Instruments and Controls 133
Midlevel English Shown, BaseLevel and Uplevel Similar
The engine oil pressure gauge
shows the engine oil pressure
in kPa (kilopascals) or psi (pounds
per square inch) when the engine is
running.
Oil pressure can vary with engine
speed, outside temperature, coolant
temperature, and oil viscosity.
On some models, the oil pump will
vary engine oil pressure according
to engine needs. Oil pressure may
change quickly as the engine speed
or load varies. This is normal. If the
oil pressure warning light or Driver Information Center (DIC) message
indicates oil pressure outside the
normal operating range, check the
vehicle's oil as soon as possible.
See
Engine Oil 0339.
Caution
Lack of proper engine oil
maintenance can damage the
engine. Driving with the engine oil
low can also damage the engine.
The repairs would not be covered
by the vehicle warranty. Check
the oil level as soon as possible.
Add oil if required, but if the oil
level is within the operating range
and the oil pressure is still low,
have the vehicle serviced. Always
follow the maintenance schedule
for changing engine oil.
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
Engine Coolant
Temperature Gauge
Midlevel Metric Shown, Base Level and Uplevel Similar
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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134 Instruments and Controls
Midlevel English Shown, BaseLevel and Uplevel Similar
This gauge measures the
temperature of the vehicle's engine
coolant.
While driving under normal
operating conditions, if the needle
moves into the red warning area,
the engine is too hot. Pull off the
road, stop the vehicle, and turn off
the engine as soon as possible.
Voltmeter Gauge
Midlevel Shown, Base Level and Uplevel Similar
When the ignition is on, this gauge
indicates the battery voltage.
When the engine is running, this
gauge shows the condition of the
charging system. The gauge can
transition from a higher to lower or a
lower to higher reading. This is
normal. If the vehicle is operating
outside the normal operating range,
the charging system light comes on.
See Charging System Light 0137. The voltmeter gauge may also read
lower when in fuel economy mode.
This is normal.
Readings outside the normal
operating range can also occur
when a large number of electrical
accessories are operating in the
vehicle and the engine is left idling
for an extended period. This
condition is normal since the
charging system is not able to
provide full power at engine idle. As
engine speeds are increased, this
condition should correct itself as
higher engine speeds allow the
charging system to create maximum
power.
The vehicle can only be driven for a
short time with the readings outside
the normal operating range. If the
vehicle must be driven, turn off all
accessories, such as the radio and
air conditioner.
Readings outside the normal
operating range indicate a possible
problem in the electrical system.
Have the vehicle serviced as soon
as possible.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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136 Instruments and Controls
The airbag readiness light comes on
for several seconds when the
vehicle is started. If the light does
not come on then, have it fixed
immediately.
{Warning
If the airbag readiness light stays
on after the vehicle is started or
comes on while driving, it means
the airbag system might not be
working properly. The airbags in
the vehicle might not inflate in a
crash, or they could even inflate
without a crash. To help avoid
injury, have the vehicle serviced
right away.
If there is a problem with the airbag
system, a Driver Information Center
(DIC) message may also come on.
Passenger Airbag Status
Indicator
The vehicle has a passenger
sensing system. See Passenger
Sensing System 077 for important safety information. The overhead
console has a passenger airbag
status indicator.
United States
Canada
When the vehicle is started, the
passenger airbag status indicator
will light ON and OFF, or the
symbols for on and off, for several
seconds as a system check. Then,
after several more seconds, the
status indicator will light either ON
or OFF, or either the on or off
symbol, to let you know the status of
the front outboard passenger frontal
airbag. If the word ON or the on symbol is
lit on the passenger airbag status
indicator, it means that the front
outboard passenger frontal airbag is
allowed to inflate.
If the word OFF or the off symbol is
lit on the passenger airbag status
indicator, it means that the
passenger sensing system has
turned off the front outboard
passenger frontal airbag.
If, after several seconds, both status
indicator lights remain on, or if there
are no lights at all, there may be a
problem with the lights or the
passenger sensing system. See
your dealer for service.
{Warning
If the airbag readiness light ever
comes on and stays on, it means
that something may be wrong
with the airbag system. To help
avoid injury to yourself or others,
have the vehicle serviced right
(Continued)