GMC SIERRA 2008 Owner's Manual

If the Light is Flashing
The following can prevent more serious damage to your
vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stops ashing and remains on steady, see “If
the Light Is On Steady” following.
If the light continues to ash, when it is safe to do so,
stop the vehicle. Find a safe place to park the vehicle.
Turn the ignition off, wait at least 10 seconds, and restart
the engine. If the light remains on steady, see “If the
Light Is On Steady” following. If the light is still ashing,
follow the previous steps and see your dealer/retailer
for service as soon as possible.
If the Light Is On Steady
You might be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. SeeFilling the Tank on page 5-10. The
diagnostic system can determine if the fuel cap hasbeen 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.
Did you just drive through a deep puddle of water?
If so, your vehicle’s electrical system might be wet. The
condition is usually corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-6. Poor fuel quality causes
the engine not to run as efficiently as designed. You
might notice this as stalling after start-up, stalling when
you put the vehicle into gear, misring, hesitation on
acceleration, or stumbling on acceleration — these
conditions might go away once the engine is warmed up.
This will be detected by the system and cause the light to
turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer/retailer can check the vehicle. Your
dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.
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Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
might begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the check
engine light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen if
you have recently replaced the battery or if the
battery has 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 you have done this and your vehicle
still does not pass the inspection for lack of OBD
system readiness, your dealer/retailer can prepare the
vehicle for inspection.
Oil Pressure Gage
Your vehicle may have an engine oil pressure gage. It
shows the engine oil pressure in psi (pounds per square
inch) when the engine is running. Canadian vehicles
indicate pressure in kPa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but if readings are outside
the normal operating range, the oil pressure light will
come on. SeeOil Pressure Light on page 3-51for more
information.United States
Canada
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A reading outside the normal operating range may be
caused by a dangerously low oil level or some other
problem causing low oil pressure. Check your oil
as soon as possible. See “OIL PRESSURE LOW” under
DIC Warnings and Messages on page 3-63and
Engine Oil (Gasoline Engine) on page 5-15.
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be
covered by your warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil.
This light will come on
briey when you start your
engine. If it does not,
have your vehicle serviced.
When the light comes on and stays on, it means that oil
is not owing through your engine properly. You
could be low on oil and you might have some other
system problem.
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Security Light
For information regarding
this light and the vehicle’s
security system, see
Content Theft-Deterrent on
page 2-18.
Fog Lamp Light
The fog lamp light will
come on when the fog
lamps are in use.
The light will go out when the fog lamps are turned off.
SeeFog Lamps on page 3-20for more information.
Cruise Control Light
This light comes on
whenever you set the
cruise control.
The light goes out when the cruise control is turned off.
SeeCruise Control on page 3-14for more information.
Highbeam On Light
This light comes on when
the high-beam headlamps
are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-11
for more information.
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Four-Wheel-Drive Light
The four-wheel-drive light
comes on when you shift a
manual transfer case
into four-wheel drive and
the front axle engages.
Some delay between the shifting and the light coming
on is normal.
SeeFour-Wheel Drive on page 2-36for more
information.
Tow/Haul Mode Light
This light comes on when
the Tow/Haul mode has
been activated.
For more information, seeTow/Haul Mode on page 2-34.
Fuel Gage
When the ignition is on, the fuel gage tells you about
how much fuel you have left in your tank.
The gage will rst indicate empty before you are out of
fuel, and you should get more fuel as soon as
possible.
When the fuel tank is low the FUEL LEVEL LOW
message will appear. SeeDIC Warnings and Messages
on page 3-63for more information.
United StatesCanada
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Here are some situations you may experience with your
fuel gage. None of these indicate a problem with the
fuel gage.
At the gas station, the fuel pump shuts off before
the gage reads full.
It takes a little more or less fuel to ll up than the
fuel gage indicated. For example, the gage may
have indicated the tank was half full, but it actually
took a little more or less than half the tank’s
capacity to ll the tank.
The gage goes back to empty when you turn off the
ignition.
If you have a diesel engine, see “Fuel Gage” in the
Diesel Engine Supplement.
Low Fuel Warning Light
This light, under the fuel
gage, will come on briey
when you are starting
the engine.This light and a chime will come on when the fuel tank
is low on fuel. There will also be a “FUEL LEVEL
LOW” message on the Driver Information Center, see
DIC Warnings and Messages on page 3-63for more
information. When you add fuel this light and message
should go off. If it does not, have your vehicle
serviced.
Driver Information Center (DIC)
Your vehicle has a Driver Information Center (DIC).
The DIC displays information about your 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.
If your vehicle has DIC buttons, see “DIC Operation and
Displays (With DIC Buttons)” later in this section and
DIC Vehicle Customization (With DIC Buttons) on
page 3-72for the displays available.
If your vehicle does not have DIC buttons, see “DIC
Operation and Displays (Without DIC Buttons)” later in
this section for the displays available.
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DIC Operation and Displays (With
DIC Buttons)
If your vehicle has DIC buttons, the information below
explains the operation of this system.
The DIC has different displays which can be accessed
by pressing the DIC buttons located on the instrument
panel, next to the steering wheel.
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.
SeeDIC Vehicle Customization (With DIC Buttons)
on page 3-72for more information.
If your vehicle has DIC buttons, you can also use the
trip odometer reset stem to view some of the DIC
displays. See “DIC Operation and Displays (Without DIC
Buttons)” later in this section.
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, and transmission temperature.
Some vehicles also display instantaneous economy and
an Active Fuel Management™ indicator.
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, and Remote Keyless Entry (RKE)
transmitter programming.
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U(Customization):Press this button to customize the
feature settings on your vehicle. SeeDIC Vehicle
Customization (With DIC Buttons) on page 3-72for 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
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 miles (mi) or kilometers (km).
Pressing the trip odometer reset stem will also display
the odometer.
To switch between English and metric 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
miles (mi) or kilometers (km) since the last reset for the
trip odometer. Pressing the trip odometer reset stem
will also display the trip odometer.
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 miles (mi) or
kilometers (km) 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 5 miles
(8 km) before it is started again, and then the
retro-active reset feature is activated, the display will
show 5 miles (8 km). As the vehicle begins moving, the
display will then increase to 5.1 miles (8.2 km),
5.2 miles (8.4 km), etc.
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Fuel Range
Press the trip/fuel button until FUEL RANGE displays.
This display shows the approximate number of
remaining miles (mi) or kilometers (km) 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 miles
per gallon (mpg) or liters per 100 kilometers (L/100 km).
This number is calculated based on the number of
mpg (L/100 km) 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 gallons (gal) or
liters (L) 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.
Timer
Press the trip/fuel button until TIMER displays. This
display can be used as a timer.
To start the timer, press the set/reset button while
TIMER is displayed. The display will show the amount
of time that has passed since the timer was last
reset, not including time the ignition is off. Time will
continue to be counted as long as the ignition is
on, even if another display is being shown on the DIC.
The timer will record up to 99 hours, 59 minutes
and 59 seconds (99:59:59) after which the display will
return to zero.
To stop the timer, press the set/reset button briey while
TIMER is displayed.
To reset the timer to zero, press and hold the set/reset
button while TIMER is displayed.
3-57

Transmission Temperature
Press the trip/fuel button until TRANS TEMP displays.
This display shows the temperature of the automatic
transmission uid in either degrees Fahrenheit (°F) or
degrees Celsius (°C).
Instantaneous Economy and Active Fuel
Management™ Indicator
If your vehicle has this display, press the trip/fuel button
until INST ECONOMY V8 MODE displays. This
display shows the current fuel economy at a particular
moment and will change frequently as driving conditions
change. This display shows the instantaneous fuel
economy in miles per gallon (mpg) or liters per
100 kilometers (L/100 km). Unlike average economy,
this screen cannot be reset.
An Active Fuel Management™ indicator will display on
the right side of the DIC, while INST ECONOMY
displays on the left side. Active Fuel Management™
allows the engine to operate on either four or eight
cylinders, depending on your driving demands. When
Active Fuel Management™ is active, V4 MODE will
display on the DIC. When Active Fuel Management™ is
inactive, V8 MODE will display. SeeActive Fuel
Management™ on page 2-27for more information.
Blank Display
This display shows no information.
Vehicle Information Menu Items
T
(Vehicle Information):Press this button to scroll
through the following menu items:
Oil Life
Press the vehicle information button until OIL LIFE
REMAINING displays. This display shows an estimate
of the oil’s remaining useful life. If you see 99% OIL LIFE
REMAINING on the display, that means 99% of the
current oil life remains. The engine oil life system
will alert you to change the oil on a schedule consistent
with your driving conditions.
When the remaining oil life is low, the CHANGE
ENGINE OIL SOON message will appear on the display.
See “CHANGE ENGINE OIL SOON” underDIC
Warnings and Messages on page 3-63. You should
change the oil as soon as you can. SeeEngine
Oil (Gasoline Engine) on page 5-15. In addition to the
engine oil life system monitoring the oil life, additional
maintenance is recommended in the Maintenance
Schedule in this manual. SeeScheduled Maintenance
(Gasoline Engine) on page 6-4for more information.
Remember, you must reset the OIL LIFE display
yourself after each oil change. It will not reset itself.
3-58