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Tire Pressure Light
For vehicles with the tire
pressure light, it comes on
briefly when the engine is
started. If it does not, have
the vehicle serviced by
your dealer/retailer.
If the system is working normally the indicator light then
goes off.
This light also comes on when one or more of the tires
is significantly underinflated.
A tire pressure message in the Driver Information
Center (DIC) can accompany the light. SeeDIC
Warnings and Messages on page 3-48for more
information.
Stop and check the tires as soon as it is safe to do so.
If underinflated, inflate the tire to the proper pressure.
SeeTires on page 5-54for more information.
If a problem is detected with the Tire Pressure Monitor
System, this light flashes for approximately 60 seconds
and then stays on for the remainder of the ignition
cycle. SeeTire Pressure Monitor System on page 5-64
for more information.
Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation
of the fuel, ignition, and emission control systems.
It ensures that emissions are at acceptable levels
for the life of the vehicle, helping to produce a cleaner
environment.
This light should come on
when the ignition is on, but
the engine is not running,
as a check to show it
working. If it does not,
have the vehicle serviced
by your dealer/retailer.
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.
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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:Modi cations 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. Modi cations 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 5-3.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, 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 flashing, 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 5-10. 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, 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.
SeeGasoline Octane on page 5-6.
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
fix 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
The oil pressure gage 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 readings above the
low pressure zone indicate the normal operating range.United States
Canada
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A reading in the low pressure zone may be caused by
a dangerously low oil level or other problem causing low
oil pressure. Check your oil as soon as possible.
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches fire.
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 fire.
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.
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This light comes on briefly 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.
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.
Security Light
For information regarding
this light and the vehicle’s
security system, see
PASS-Key
®III+ Electronic
Immobilizer Operation
on page 2-17.
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 3-9for more information.
Highbeam On Light
This light comes on when
the high-beam headlamps
are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-8
for more information.
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Tow/Haul Mode Light
This light comes on when
the Tow/Haul mode has
been activated.
For more information, seeTow/Haul Mode on page 2-25.
Fuel Gage
The fuel gage, when the ignition is on, indicates how
much fuel is left in the vehicle’s fuel tank.An arrow on the fuel gage indicates the side of the
vehicle the fuel door is on.
The gage first indicates empty before the vehicle is out
of fuel, and the fuel tank should be refueled soon.
Listed are four situations customers might 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 fill 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 fill the tank.
•The gage moves a little while turning a corner or
speeding up.
•The gage does not go back to empty when the
ignition is turned off.
If the vehicle has the DURAMAX Diesel engine, see the
DURAMAX Diesel manual for more information.
United StatesCanada
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To adjust for compass variance, use the following
procedure:
Compass Variance (Zone) Procedure
1. Do not set the compass zone when the vehicle is
moving. Only set it when the vehicle is in P (Park).
Press the vehicle information button until
PRESS
VTO CHANGE COMPASS ZONE displays.
2. Find the vehicle’s current location and variance
zone number on the map.
Zones 1 through 15 are available.3. Press the set/reset button to scroll through and
select the appropriate variance zone.
4. Press the trip/fuel button until the vehicle heading,
for example, N for North, is displayed in the DIC.
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 field
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.
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