2009 GMC SIERRA 1500 light

If the check engine light 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, after a while, the emission controls might
not work as well, the vehicle’s 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:Modications 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.
Modications 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.
SeeAccessories and Modifications on page 5-4.This light comes on during a malfunction in one of
two ways:
Light Flashing:A misre condition has been detected.
A misre 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 ash, when it is safe to do so, stop
the vehicle. Find a safe place to park the vehicle. Turn the
key off, wait at least 10 seconds, and restart the engine.
If the light is still ashing, follow the previous steps and
see your dealer/retailer for service as soon as possible.
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Light On Steady:An emission control system
malfunction has been detected on the vehicle.
Diagnosis and service might be required.
An emission system malfunction might be corrected by
doing the following:
Make sure the fuel cap is fully installed. SeeFilling
the Tank on page 5-11. 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.
If the vehicle has been driven through a deep puddle
of water, the 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.
Make sure to fuel the vehicle with quality fuel. Poor
fuel quality causes the engine not to run as efficiently
as designed and can cause: stalling after start-up,
stalling when the vehicle is changed into gear,
misring, 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.
SeeGasoline Octane on page 5-7.
If none of the above have made the light turn off, your
dealer/retailer can check the vehicle. The 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 the vehicle. Failure to pass this inspection
could prevent getting a vehicle registration.
Here are some things to know to help the vehicle pass
an inspection:
The vehicle will not pass this inspection if the check
engine light is on with the engine running, or if the
key is in ON/RUN and the light is not on.
The vehicle will not pass this inspection if the OBD II
(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 the battery has recently been replaced 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 this has been done and the
vehicle still does not pass the inspection for lack of
OBD II system readiness, your dealer/retailer can
prepare the vehicle for inspection.
Oil Pressure Gage (US-Canada)
For vehicles with 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 can vary with engine speed, outside
temperature and oil viscosity, but if readings are outside
the normal operating range, the oil pressure light
comes on. SeeOil Pressure Light on page 3-49for
more information.United States
Canada
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A reading outside the normal operating range can be
caused by a dangerously low oil level or some other
problem causing low oil pressure. Check the vehicle’s oil
as soon as possible. See “OIL PRESSURE LOW” under
DIC Warnings and Messages on page 3-66andEngine
Oil on page 5-17.
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance
can damage the engine. The repairs would not be
covered by the vehicle 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.
The engine can become so hot that it catches re.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance
can damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
This light comes on briey while starting the engine. If it
does not, have the vehicle serviced by your dealer/
retailer. If the system is working normally the indicator
light then goes off.
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If the light comes on and stays on, it means that oil is not
owing through the engine properly. The vehicle could be
low on oil and it might have some other system problem.
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 comes
on when the fog lamps are
in use.
The light goes out when the fog lamps are turned off.
SeeFog Lamps on page 3-19for more information.
Cruise Control Light
The cruise control light
comes on whenever the
cruise control is set.
The light goes out when the cruise control is turned off.
SeeCruise Control on page 3-12for more information.
Highbeam On Light
This light comes on when
the high-beam headlamps
are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-10
for more information.
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Four-Wheel-Drive Light
The four-wheel-drive light
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.
SeeFour-Wheel Drive on page 2-37for 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 shows about how
much fuel is left in the fuel tank.
An arrow on the fuel gage indicates the side of the
vehicle the fuel door is on.
The gage will rst indicate empty before the vehicle is
out of fuel, but the vehicle’s fuel tank should be
lled soon.
When the fuel tank is low the FUEL LEVEL LOW
message appears. SeeDIC Warnings and Messages on
page 3-66for more information.
United StatesCanada
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Here are some situations owners can experience with
the 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 fuel tank’s
capacity to ll it.
The gage goes back to empty when the ignition is
turned off.
For a diesel engine, see “Fuel Gage” in the Diesel
Engine Supplement.
Low Fuel Warning Light
This light, under the fuel
gage, comes on briey
while the engine is being
started.
This light and a chime comes on when the fuel tank is low
on fuel. The Driver Information Center also displays a
“FUEL LEVEL LOW” message. SeeDIC Warnings and
Messages on page 3-66for more information. When fuel
is added this light and message should go off. If it does
not, have the vehicle serviced by your dealer/retailer.
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4. Press the trip/fuel button until the vehicle heading, for
example, N for North, is displayed in the DIC. Or, if
the vehicle does not have DIC buttons, press and
hold the trip odometer reset stem for two seconds to
select the next available variance zone. Repeat this
step until the appropriate variance zone is displayed.
5. If calibration is necessary, calibrate the compass.
See “Compass Calibration Procedure” following.
Compass Calibration
The compass can be manually calibrated. Only calibrate
the compass in a magnetically clean and safe location,
such as an open parking lot, where driving the vehicle in
circles is not a danger. It is suggested to calibrate away
from tall buildings, utility wires, manhole covers, or other
industrial structures, if possible.
If CAL should ever appear in the DIC display, the
compass should be calibrated.
If the DIC display does not show a heading, for example,
N for North, or the heading does not change after making
turns, there may be a strong magnetic eld interfering
with the compass. Such interference may be caused by a
magnetic CB or cell phone antenna mount, a magnetic
emergency light, magnetic note pad holder, or any other
magnetic item. Turn off the vehicle, move the magnetic
item, then turn on the vehicle and calibrate the compass.To calibrate the compass, use the following procedure:
Compass Calibration Procedure
1. Before calibrating the compass, make sure the
compass zone is set to the variance zone in which
the vehicle is located. See “Compass Variance
(Zone) Procedure” earlier in this section.
Do not operate any switches such as window,
sunroof, climate controls, seats, etc. during
the calibration procedure.
2. Press the vehicle information button until PRESS
V
TO CALIBRATE COMPAS (Compass) displays. Or,
if the vehicle does not have DIC buttons, press the
trip odometer reset stem until CALIBRATE
COMPASS displays.
3. Press the set/reset button to start the compass
calibration. Or, if the vehicle does not have DIC
buttons, press and hold the trip odometer reset stem
for two seconds to start the compass calibration.
4. The DIC will display CALIBRATING: DRIVE IN
CIRCLES. Drive the vehicle in tight circles at less
than 5 mph (8 km/h) to complete the calibration. The
DIC will display CALIBRATION COMPLETE for a
few seconds when the calibration is complete. The
DIC display will then return to the previous menu.
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