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Instruments and Controls 121
When the vehicle is started, these lights
come on solid to remind rear passengers to
fasten their seat belts. Then each light may
stay on solid or flash, and a chime may
come on if the rear passenger remains
unbuckled, or becomes unbuckled, when the
vehicle is moving. An X indicates the seat
belt is not buckled. A check mark indicates
the seat belt is buckled.
If all rear seat positions are buckled, neither
the chime nor the lights will come on.
For information on the front seat belt
reminder lights, see "Driver Seat Belt
Reminder Light" and "Front Passenger Seat
Belt Reminder Light" listed previously.
Airbag Readiness Light
This light shows if there is an electrical
problem with the airbag system. It is
located in the instrument cluster. The
system check includes the airbag sensor(s),
the passenger sensing system, the
pretensioners, the airbag modules, the
wiring, and the crash sensing and diagnostic
module. For more information on the airbag
system, seeAirbag System 064.
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 069 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
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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122 Instruments and Controls
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, or if the airbag readiness light
is on, there may be a problem with the
lights or the passenger sensing system. See
your dealer for service right away.
{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)
Warning (Continued)
away. SeeAirbag Readiness Light 0121
for more information, including important
safety information.
Charging System Light
The charging system light comes on briefly
when the ignition is turned on, but the
engine is not running, as a check to show
the light is working. It should go out when
the engine is started.
If the light stays on, or comes on while
driving, there may be a problem with the
electrical charging system. Have it checked
by your dealer. Driving while this light is on
could drain the battery.
When this light comes on, or is flashing, the
Driver Information Center (DIC) also displays
a message. If a short distance must be driven with the
light on, be sure to turn off all accessories,
such as the radio and air conditioner. Find a
safe place to stop the vehicle.
Malfunction Indicator Lamp
(Check Engine Light)
This light is part of the vehicle’s emission
control on-board diagnostic system. If this
light is on while the engine is running, a
malfunction has been detected and the
vehicle may require service. The light should
come on to show that it is working when
the ignition is on and the engine is not
running. See
Ignition Positions 0216.
Malfunctions are often indicated by the
system before any problem is noticeable.
Being aware of the light and seeking service
promptly when it comes on may prevent
damage.
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Instruments and Controls 139
The windshield is part of the HUD system.
SeeWindshield Replacement 0332.
Vehicle Messages
Messages displayed on the Driver
Information Center (DIC) indicate the status
of the vehicle or some action that may be
needed to correct a condition. Multiple
messages may appear one after another.
The messages that do not require
immediate action can be acknowledged and
cleared by pressing the thumbwheel. The
messages that require immediate action
cannot be cleared until that action is
performed.
All messages should be taken seriously;
clearing the message does not correct the
problem.
If a SERVICE message appears, see your
dealer.
Follow the instructions given in the
messages. The system displays messages
regarding the following topics:
.Service Messages
.Fluid Levels
.Vehicle Security
.Brakes
.Steering
.Ride Control Systems
.Advanced Driver Assistance Systems
.Cruise Control
.Lighting and Bulb Replacement
.Wiper/Washer Systems
.Doors and Windows
.Seat Belts
.Airbag Systems
.Engine and Transmission
.Tire Pressure
.Battery
Engine Power Messages
REDUCED ACCELERATION DRIVE
WITH CARE
This message displays when the vehicle's
propulsion power is reduced. A reduction in
propulsion power can affect the vehicle's
ability to accelerate. If this message is on,
but there is no observed reduction in
performance, proceed to your destination.
Under certain conditions the performance
may be reduced the next time the vehicle is
driven. The vehicle may be driven while this
message is on, but maximum acceleration
and speed may be reduced. Anytime this message stays on, or displays repeatedly,
the vehicle should be taken to your dealer
for service as soon as possible.
Under certain operating conditions,
propulsion will be disabled. Try restarting
after the ignition has been off for
two minutes.
Vehicle Speed Messages
SPEED LIMITED TO XXX KM/H (MPH)
This message shows that the vehicle speed
has been limited to the speed displayed. The
limited speed is a protection for various
propulsion and vehicle systems, such as
lubrication, thermal, brakes, suspension,
Teen Driver if equipped, or tires.
(If equipped with a diesel engine, see the
Duramax Diesel supplement.)
–For Diesel
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Driving and Operating 217
near a strong radio antenna signal causing
interference to the Keyless Access system.
SeeRemote Key Operation 015.
To shift out of P (Park), the vehicle must be
on and the brake pedal must be applied.
{Warning
Turning off the vehicle while moving may
cause loss of power assist in the brake
and steering systems and disable the
airbags. While driving, only shut the
vehicle off in an emergency.
Stopping the Engine/LOCK/OFF (No Indicator
Lights) : When the vehicle is stopped, press
ENGINE START/STOP once to turn the
engine off.
If the vehicle is in P (Park), the vehicle will
turn off, and Retained Accessory Power (RAP)
will remain active. See Retained Accessory
Power (RAP) 0220.
If the vehicle is not in P (Park), the vehicle
will return to accessory mode and display
the message SHIFT TO PARK in the Driver
Information Center (DIC). When the vehicle is
shifted into P (Park), the vehicle will turn off. The vehicle may have an electric steering
column lock. The lock is activated when the
ignition is turned off and driver door is
opened. A sound may be heard as the lock
actuates or releases. The steering column
lock may not release with the wheels turned
off center. If this happens, the vehicle may
not start. Move the steering wheel from left
to right while attempting to start the
vehicle. If this does not work, the vehicle
needs service.
Unless an emergency exists, do not turn the
engine off when the vehicle is moving. This
will cause a loss of power assist in the brake
and steering systems and disable the
airbags.
If the vehicle must be shut off in an
emergency:
1. If the vehicle cannot be pulled over, and must be shut off while driving, press and
hold ENGINE START/STOP button for
longer than two seconds, or press twice
in five seconds.
2. Brake using a firm and steady pressure. Do not pump the brakes repeatedly. This
may deplete power assist, requiring
increased brake pedal force. 3. Shift the vehicle to N (Neutral). This can
be done while the vehicle is moving.
After shifting to N (Neutral), firmly apply
the brakes and steer the vehicle to a
safe location.
4. Come to a complete stop, shift to P (Park), and make sure engine is off.
The shift lever must be in P (Park) to
turn the vehicle off.
5. Set the parking brake. See Electric
Parking Brake 0234.
{Warning
Turning off the vehicle while moving may
cause loss of power assist in the brake
and steering systems and disable the
airbags. While driving, only shut the
vehicle off in an emergency.
Accessory Mode (Amber Indicator Light) :
This mode allows some electrical accessories
to be used when the engine is off.
With the vehicle off, pressing the ENGINE
START/STOP button one time without the
brake pedal applied will place the vehicle in
accessory mode.
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306 Driving and Operating
If Tow/Haul Mode is off and this setting is
on for a Trailer Profile, each time the vehicle
is turned on, a reminder will appear in the
DIC to turn on Tow/Haul Mode when the
Trailer Profile is active.
If Tow/Haul Mode is on and this setting is
on for a Trailer Profile, the reminder will not
appear when the Trailer Profile is active.
Conversions and Add-Ons
Add-On Electrical Equipment
{Warning
The Data Link Connector (DLC) is used for
vehicle service and Emission Inspection/
Maintenance testing. SeeMalfunction
Indicator Lamp (Check Engine Light) 0122.
A device connected to the DLC —such as
an aftermarket fleet or driver-behavior
tracking device —may interfere with
vehicle systems. This could affect vehicle
operation and cause a crash. Such devices
may also access information stored in the
vehicle’s systems.
Caution
Some electrical equipment can damage
the vehicle or cause components to not
work and would not be covered by the
vehicle warranty. Always check with your
dealer before adding electrical equipment.
Add-on equipment can drain the vehicle's
12-volt battery, even if the vehicle is not
operating.
The vehicle has an airbag system. Before
attempting to add anything electrical to the
vehicle, see Servicing the Airbag-Equipped
Vehicle 073 and
Adding Equipment to the Airbag-Equipped
Vehicle 073.
For information on wiring auxiliary switches,
see www.gmupfitter.com or contact your
dealer.
Adding a Snow Plow or Similar
Equipment
Caution
Do not exceed 72 km/h (45 mph) with a
snow plow mounted to the vehicle. The
vehicle could overheat and be damaged.
Before installing a snow plow on the vehicle,
follow these guidelines:
Caution
If the vehicle does not have the snow
plow prep package, RPO VYU, adding a
plow can damage the vehicle, and the
repairs would not be covered by the
vehicle warranty. Unless the vehicle was
built to carry a snow plow, do not add
one to the vehicle. If the vehicle has RPO
VYU, then the payload the vehicle can
carry will be reduced when a snow plow
is installed. The vehicle can be damaged
if either the front or rear axle ratings or
the Gross Vehicle Weight Rating (GVWR)
are exceeded.
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310 Vehicle Care
Towing the Vehicle
Transporting a Disabled Vehicle . . . . . . . 379
Recreational Vehicle Towing . . . . . . . . . . . 380
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . 383
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . 388
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 391
General Information
For service and parts needs, visit your
dealer. You will receive genuine GM parts
and GM-trained and supported service
people.
Genuine GM parts have one of these marks:
California Perchlorate Materials
Requirements
Certain types of automotive applications,
such as airbag initiators, seat belt
pretensioners, and lithium batteries
contained in electronic keys, may contain
perchlorate materials. Perchlorate Material–
special handling may apply. See
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and Modifications
Adding non-dealer accessories or making
modifications to the vehicle can affect
vehicle performance and safety, including
such things as airbags, braking, stability,
ride and handling, emissions systems,
aerodynamics, durability, Advanced Driver
Assistance Systems, and electronic systems
like antilock brakes, traction control, and
stability control. These accessories or
modifications could even cause malfunction
or damage not covered by the vehicle
warranty.
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Caution
When adding accessories or other
equipment after the purchase of your
vehicle, ensure you are not exceeding the
vehicle axle weight ratings or overall
weight ratings. Overloading the vehicle
may cause damage. Repairs would not be
covered by the vehicle warranty. Do not
overload the vehicle. SeeVehicle Load
Limits 0210 and
Trailer Towing 0280 for those specific
weight ratings.
Damage to suspension components caused
by modifying vehicle height outside of
factory settings will not be covered by the
vehicle warranty.
Damage to vehicle components resulting
from modifications or the installation or use
of non-GM certified parts, including control
module or software modifications, is not
covered under the terms of the vehicle
warranty and may affect remaining
warranty coverage for affected parts. GM Accessories are designed to complement
and function with other systems on the
vehicle. See your dealer to accessorize the
vehicle using genuine GM Accessories
installed by a dealer technician.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle 073.
Vehicle Checks
Doing Your Own Service Work
{Warning
It can be dangerous to work on your
vehicle if you do not have the proper
knowledge, service manual, tools,
or parts. Always follow owner’s manual
procedures and consult the service
manual for your vehicle before doing any
service work. If doing some of your own service work, use
the proper service manual. It tells you much
more about how to service the vehicle than
this manual can. To order the proper service
manual, see
Publication Ordering
Information 0413.
This vehicle has an airbag system. Before
attempting to do your own service work,
see Servicing the Airbag-Equipped Vehicle
0 73.
If equipped with remote vehicle start, open
the hood before performing any service
work to prevent remote starting the vehicle
accidentally. See Remote Vehicle Start 021.
Keep a record with all parts receipts and list
the mileage and the date of any service
work performed. See Maintenance Records
0 400.
Caution
Even small amounts of contamination can
cause damage to vehicle systems. Do not
allow contaminants to contact the fluids,
reservoir caps, or dipsticks.
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Vehicle Care 361
If the vehicle tires must be replaced
with a tire that does not have a TPC
Spec number, make sure they are the
same size, load range, speed rating, and
construction (radial) as the original
tires.
The Tire and Loading Information label
indicates the original equipment tires
on the vehicle. SeeVehicle Load Limits
0 210.
Different Size Tires and Wheels
If wheels or tires are installed that are a
different size than the original equipment
wheels and tires, vehicle performance,
including its braking, ride and handling
characteristics, stability, and resistance to
rollover may be affected. If the vehicle has
electronic systems such as antilock brakes,
rollover airbags, traction control, electronic
stability control, or All-Wheel Drive, the
performance of these systems can also be
affected.
{Warning
If different sized wheels are used, there
may not be an acceptable level of
performance and safety if tires not
recommended for those wheels are
selected. This increases the chance of a
crash and serious injury. Only use GM
specific wheel and tire systems developed
for the vehicle, and have them properly
installed by a GM certified technician.
See Buying New Tires 0360 and
Accessories and Modifications 0310.
Uniform Tire Quality Grading
The following information relates to the
system developed by the United States
National Highway Traffic Safety
Administration (NHTSA), which grades
tires by treadwear, traction, and
temperature performance. This applies
only to vehicles sold in the United
States. The grades are molded on the
sidewalls of most passenger car tires.
The Uniform Tire Quality Grading
(UTQG) system does not apply to deep
tread, winter tires, compact spare tires, tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General
Motors passenger cars and light trucks
may vary with respect to these grades,
they must also conform to federal
safety requirements and additional
General Motors Tire Performance
Criteria (TPC) standards.
Quality grades can be found where
applicable on the tire sidewall between
tread shoulder and maximum section
width. For example:Treadwear 200 Traction AA Temperature A
All Passenger Car Tires Must Conform to
Federal Safety Requirements In Addition
To These Grades.
Treadwear
The treadwear grade is a comparative
rating based on the wear rate of the
tire when tested under controlled
conditions on a specified government
test course. For example, a tire graded
150 would wear one and one-half (1½)