GMC SIERRA 1500 2012 Owners Manual

Black plate (23,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-23
If the malfunction indicator lamp
comes on and stays on while the
engine is running, this indicates that
there is an OBD II problem and
service is required.
Malfunctions often are indicated by
the system before any problem is
apparent. Being aware of the light
can prevent more serious damage
to the vehicle. This system assists
the service technician in correctly
diagnosing any malfunction.
Notice:If the vehicle is
continually driven with this light
on, the emission controls might
not work as well, the vehicle fuel
economy might not be as good,
and the engine might not run as
smoothly. This could lead to
costly repairs that might not be
covered by the vehicle warranty. Notice:
Modifications made
to the engine, transmission,
exhaust, intake, or fuel system
of the vehicle or the replacement
of the original tires with other
than those of the same Tire
Performance Criteria (TPC) can
affect the vehicle's emission
controls and can cause this light
to come on. Modifications to
these systems could lead to
costly repairs not covered by
the vehicle warranty. This could
also result in a failure to pass a
required Emission Inspection/
Maintenance test. See
Accessories and Modifications on
page 10‑3.
This light comes on during a
malfunction in one of two ways:
Light Flashing: A misfire condition
has been detected. A misfire
increases vehicle emissions and
could damage the emission control
system on the vehicle. Diagnosis
and service might be required. To prevent more serious damage to
the vehicle:
.Reduce vehicle speed.
.Avoid hard accelerations.
.Avoid steep uphill grades.
.If towing a trailer, reduce the
amount of cargo being hauled as
soon as it is possible.
If the light continues to flash, stop
and park the vehicle. Turn the
vehicle off, wait at least 10 seconds,
and restart the engine. If the light is
still flashing, follow the previous
steps and see your dealer for
service as soon as possible.
Light On Steady: An emission
control system malfunction has
been detected on the vehicle.
Diagnosis and service might be
required.

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5-24 Instruments and Controls
The following may correct an
emission system malfunction:
.Check that the fuel cap is fully
installed. SeeFilling the Tank on
page 9‑72. The diagnostic
system can determine if the
fuel cap has been left off or
improperly installed. A loose or
missing fuel cap allows fuel to
evaporate into the atmosphere.
A few driving trips with the cap
properly installed should turn the
light off.
.Check that good quality fuel is
used. Poor fuel quality causes
the engine not to run as
efficiently as designed and may
cause stalling after start-up,
stalling when the vehicle is
changed into gear, misfiring,
hesitation on acceleration,
or stumbling on acceleration.
These conditions might go away
once the engine is warmed up. If one or more of these conditions
occurs, change the fuel brand used.
It will require at least one full tank of
the proper fuel to turn the light off.
See
Recommended Fuel on
page 9‑68.
If none of the above have made
the light turn off, your dealer can
check the vehicle. The dealer has
the proper test equipment and
diagnostic tools to fix any
mechanical or electrical problems
that might have developed.Emissions Inspection and
Maintenance Programs
Some local governments may have
programs to inspect the on-vehicle
emission control equipment. For
the inspection, the emission system
test equipment is connected
to the vehicle’s Data Link
Connector (DLC).
The DLC is under the instrument
panel to the left of the steering
wheel. See your dealer if assistance
is needed.
The vehicle may not pass
inspection if:
.The malfunction indicator lamp is
on with the engine running, or if
the light does not come on when
the ignition is turned to ON/RUN
while the engine is off. See
your dealer for assistance in
verifying proper operation of the
malfunction indicator lamp.
.The OBD II (On-Board
Diagnostics) system
determines that critical
emission control systems have
not been completely diagnosed.

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Instruments and Controls 5-25
The vehicle would be considered
not ready for inspection. This
can happen if the 12-volt battery
has recently been replaced or
run down. The diagnostic system
is designed to evaluate critical
emission control systems during
normal driving. This can take
several days of routine driving.
If this has been done and the
vehicle still does not pass the
inspection for lack of OBD II
system readiness, your dealer
can prepare the vehicle for
inspection.
Brake System Warning
Light
With the ignition on, the brake
system warning light comes on
when the parking brake is set. If the
vehicle is driven with the parking
brake engaged, a chime sounds
when the vehicle speed is greater
than 8 km/h (5 mph).The vehicle brake system consists
of two hydraulic circuits. If one
circuit is not working, the remaining
circuit can still work to stop the
vehicle. For normal braking
performance, both circuits need to
be working.
If the warning light comes on and a
chime sounds there could be a
brake problem. Have the brake
system inspected right away.
This light can also come on due to
low brake fluid. See
Brake Fluid on
page 10‑28 for more information.
MetricEnglish
This light comes on briefly when the
ignition key is turned to ON/RUN.
If it does not come on then, have it
fixed so it is ready to warn if there is
a problem.
{WARNING
The brake system might not be
working properly if the brake
system warning light is on.
Driving with the brake system
warning light on can lead to a
crash. If the light is still on after
the vehicle has been pulled off
the road and carefully stopped,
have the vehicle towed for
service.
If the light comes on while driving,
pull off the road and stop carefully.
The pedal might be harder to push
or might go closer to the floor. It can
take longer to stop. If the light is
still on, have the vehicle towed for
service. See Towing the Vehicle on
page 10‑93.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.

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5-26 Instruments and Controls
Antilock Brake System
(ABS) Warning Light
For vehicles with the Antilock Brake
System (ABS), this light comes on
briefly when the engine is started.
If it does not, have the vehicle
serviced by your dealer. If the
system is working normally the
indicator light then goes off.
If the ABS light stays on, turn the
ignition off. If the light comes on
while driving, stop as soon as it is
safely possible and turn the ignition
off. Then start the engine again to
reset the system. If the ABS light
stays on, or comes on again while
driving, the vehicle needs service.
If the regular brake system warning
light is not on, the vehicle still has
brakes, but not antilock brakes.If the regular brake system warning
light is also on, the vehicle does not
have antilock brakes and there is a
problem with the regular brakes.
See
Brake System Warning Light on
page 5‑25.
For vehicles with a Driver
Information Center (DIC), see Brake
System Messages on page 5‑40 for
all brake‐related DIC messages.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Four-Wheel-Drive Light
For vehicles equipped with the
four-wheel-drive light, it comes on
when a vehicle with a manual transfer case is shifted into
four-wheel drive and the front axle
engages.
Some delay between the shifting
and the light coming on is normal.
See
Four-Wheel Drive on page 9‑40
for more information.
Tow/Haul Mode Light
For vehicles with the Tow/Haul
Mode feature, this light comes on
when the Tow/Haul Mode has been
activated.
For more information, see Tow/Haul
Mode on page 9‑39.

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Instruments and Controls 5-27
StabiliTrak®OFF Light
This light comes on briefly while
starting the engine.
If it does not, have the vehicle
serviced by your dealer. If the
system is working normally, the
indicator light then goes off.
Press and release the Traction
Control System (TCS)/StabiliTrak
button to turn off TCS, and a
message displays in the DIC.
Press and briefly hold the TCS/
StabiliTrak button to turn off the
StabiliTrak system; the StabiliTrak
Off light comes on and a message
appears in the Driver Information
Center (DIC).If the StabiliTrak/TCS system is
off, the system does not assist in
controlling the vehicle. Turn on the
StabiliTrak/TCS system and the
indicator light turns off.
See
StabiliTrak
®System on
page 9‑55, and Ride Control System
Messages on page 5‑44 for more
information.
Traction Control System
(TCS)/StabiliTrak®Light
The TCS/StabiliTrak light comes on
briefly when the engine is started.
If the light does not come on or
stays on, have the vehicle serviced
by the dealer. If the system is
working normally, the indicator light
turns off. If the light comes on and stays
on while driving, and a message
displays in the Driver Information
Center (DIC), have the vehicle
serviced by the dealer. See
Ride
Control System Messages on
page 5‑44 for more information.
If the light flashes while driving, this
means that StabiliTrak or TCS is
assisting in controlling the vehicle.
See StabiliTrak
®System on
page 9‑55 for more information.
Tire Pressure Light
For vehicles with the Tire Pressure
Monitor System (TPMS), this light
comes on briefly when the engine
is started. It provides information
about tire pressures and the TPMS.

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5-28 Instruments and Controls
When the Light Is On Steady
This indicates that one or more
of the tires are significantly
underinflated.
A Driver Information Center (DIC)
tire pressure message may also
display. SeeTire Messages on
page 5‑45. Stop as soon as
possible, and inflate the tires to the
pressure value shown on the Tire
and Loading Information label. See
Tire Pressure on page 10‑58.
When the Light Flashes First and
Then Is On Steady
If the light flashes for about a minute
and then stays on, there may be a
problem with the TPMS. If the
problem is not corrected, the light
will come on at every ignition
cycle. See Tire Pressure Monitor
Operation on page 10‑62.Engine Oil Pressure Light
Notice: 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.
This light comes on briefly while
starting the engine. If it does not,
have the vehicle serviced by your
dealer. If the system is working
normally the indicator light then
goes off. If the light comes on and stays on, it
means that oil is not flowing through
the engine properly. The vehicle
could be low on oil and it might
have some other system problem.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Low Fuel Warning Light
This light, under the fuel gauge,
comes on briefly while the engine is
being started.
This light and a chime, if the vehicle
is equipped with a radio, comes on
when the fuel tank is low on fuel.
The Driver Information Center also
displays a FUEL LEVEL LOW
message. See
Fuel System
Messages on page 5‑43 for more

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Instruments and Controls 5-29
information. When fuel is added this
light and message should go off. If it
does not, have the vehicle serviced
by your dealer.
Security Light
The security light should come on
briefly as the engine is started. If the
system is working normally, the
indicator light turns off. If it does not
come on, have the vehicle serviced
by your dealer.
If the light stays on and the engine
does not start, there could be a
problem with the theft-deterrent
system.This light is also used to indicate the
status of the anti-theft alarm system
when the ignition is turned off. The
light will flash rapidly if the alarm
system is arming and one or more
of the monitored entry points is not
closed. The light will stay on if the
alarm is arming and all entry points
are closed.
For information regarding this light
and the vehicle's security system,
see
Anti-theft Alarm System on
page 2‑11.High-Beam On Light
This light comes on when the
high-beam headlamps are in use.
See Headlamp High/Low-Beam
Changer on page 6‑3.
Front Fog Lamp Light
For vehicles with fog lamps, this
light comes on when the fog lamps
are on.
The light goes out when the fog
lamps are turned off. See Fog
Lamps on page 6‑6 for more
information.

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5-30 Instruments and Controls
Cruise Control Light
For vehicles equipped with cruise
control, this light comes on
whenever the cruise control is set.
The light goes out when the cruise
control is turned off. SeeCruise
Control on page 9‑58 for more
information.
Information Displays
Driver Information
Center (DIC)
The vehicle has a Driver Information
Center (DIC).
The DIC displays information about
this vehicle. It also displays warning
messages if a system problem is
detected.
All messages will appear in
the DIC display located below the
tachometer in the instrument panel
cluster.
The DIC comes on when the ignition
is on. After a short delay, the DIC
will display the information that was
last displayed before the engine
was turned off. The DIC has different displays
which can be accessed by pressing
the DIC buttons located on the
instrument panel, next to the
steering wheel. If the vehicle does
not have DIC buttons, the trip
odometer reset stem can be used to
access some of the menu items.
The DIC displays trip, fuel, and
vehicle system information, and
warning messages if a system
problem is detected.
The DIC also allows some features
to be customized. See
Vehicle
Personalization (With DIC Buttons)
on page 5‑48 for more information.
If the vehicle has a diesel
engine, see the Duramax
®diesel
supplement for more information.

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Instruments and Controls 5-31
DIC Buttons
The buttons are the trip/fuel, vehicle
information, customization, and set/
reset buttons. The button functions
are detailed in the following pages.
3(Trip/Fuel):Press this button
to display the odometer, trip
odometer, fuel range, average
economy, fuel used, timer,
transmission temperature, and
instantaneous economy and Active
Fuel Management™ indicator. The
compass and outside temperature
will also be shown in the display. The temperature will be shown
in °C or °F depending on the units
selected.
T(Vehicle Information):
Press
this button to display the oil life,
units, tire pressure readings for
vehicles with the Tire Pressure
Monitor System (TPMS), trailer
brake gain and output information
for vehicles with the Integrated
Trailer Brake Control (ITBC) system,
engine hours, compass zone
setting, and compass recalibration.
U(Customization): Press this
button to customize the feature
settings on the vehicle. See Vehicle
Personalization (With DIC Buttons)
on page 5‑48 for more information.
V(Set/Reset):Press this button to
set or reset certain functions and to
turn off or acknowledge messages
on the DIC.
Trip/Fuel Menu Items (with DIC
Buttons)
3(Trip/Fuel): Press this button
to scroll through the following menu
items:
Odometer
Press the trip/fuel button until
ODOMETER displays. This display
shows the distance the vehicle has
been driven in either kilometers (km)
or miles. Pressing the trip odometer
reset stem will also display the
odometer.
To switch between metric and
English measurements, see “Units”
later in this section.
Trip Odometer
Press the trip/fuel button until TRIP
displays. This display shows the
current distance traveled in either
kilometers (km) or miles since the
last reset for the trip odometer.
Pressing the trip odometer reset
stem will also display the trip
odometer.

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The trip odometer can be reset to
zero by pressing the set/reset
button while the trip odometer is
displayed. You can also reset the
trip odometer while it is displayed by
pressing and holding the trip
odometer reset stem.
The trip odometer has a feature
called the retro-active reset. This
can be used to set the trip odometer
to the number of miles (kilometers)
driven since the ignition was last
turned on. This can be used if the
trip odometer is not reset at the
beginning of the trip.
To use the retro-active reset feature,
press and hold the set/reset button
for at least four seconds. The trip
odometer will display the number of
kilometers (km) or miles driven since
the ignition was last turned on and
the vehicle was moving. Once the
vehicle begins moving, the trip
odometer will accumulate mileage.
For example, if the vehicle was
driven 8 km (5 miles) before it is
started again, and then the
retro-active reset feature isactivated, the display will show 8 km
(5 miles). As the vehicle begins
moving, the display will then
increase to 8.2 km (5.1 miles),
8.4 km (5.2 miles), etc.
Fuel Range
Press the trip/fuel button until FUEL
RANGE displays. This display
shows the approximate number of
remaining kilometers (km) or miles
the vehicle can be driven without
refueling. The display will show
LOW if the fuel level is low.
The fuel range estimate is based on
an average of the vehicle's fuel
economy over recent driving history
and the amount of fuel remaining in
the fuel tank. This estimate will
change if driving conditions change.
For example, if driving in traffic and
making frequent stops, this display
may read one number, but if the
vehicle is driven on a freeway, the
number may change even though
the same amount of fuel is in the
fuel tank. This is because different
driving conditions produce different
fuel economies. Generally, freeway
driving produces better fuel
economy than city driving. Fuel
range cannot be reset.
Average Economy
Press the trip/fuel button until AVG
ECONOMY displays. This display
shows the approximate average
liters per 100 kilometers (L/100 km)
or miles per gallon (mpg). This
number is calculated based on the
number of L/100 km (mpg) recorded
since the last time this menu
item was reset. To reset AVG
ECONOMY, press and hold the set/
reset button.
Fuel Used
Press the trip/fuel button until
FUEL USED displays. This display
shows the number of liters (L) or
gallons (gal) of fuel used since the
last reset of this menu item. To reset
the fuel used information, press and
hold the set/reset button while FUEL
USED is displayed.