2003 GMC YUKON fuel

Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. The Check Engine light comes on to
indicate that there is a problem and service is required.
Malfunctions often will be indicated by the system
before any problem is apparent. This may prevent more
serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after a while, your emission controls
may not work as well, your fuel economy may not
be as good and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.Notice:Modications made to the engine,
transmission, exhaust, intake or fuel system of your
vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is
not running. If the light doesn’t come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
•Light Flashing—Amisfire condition has been
detected. A misfire increases vehicle emissions
and may damage the emission control system on
your vehicle. Diagnosis and service may be
required.
•Light On Steady—An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
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If the Light is Flashing
The following may prevent more serious damage to
your vehicle:
•Reducing vehicle speed.
•Avoiding hard accelerations.
•Avoiding 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 stopsflashing and remains on steady, see“If
the Light Is On Steady”following.
If the light continues toflash, when it is safe to do so,
stop the vehicle.Find a safe place to park your vehicle.
Turn the key 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
flashing, follow the previous steps, and see your dealer
for service as soon as possible.
If the Light Is On Steady
You may 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 Your Tank on page 5-7. The
diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap will allow 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 electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
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Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-4. Poor fuel quality will
cause your engine not to run as efficiently as designed.
You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, misfiring, hesitation
on acceleration or stumbling on acceleration. (These
conditions may 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 can check the vehicle. Your dealer has the
proper test equipment and diagnostic tools tofix any
mechanical or electrical problems that may have
developed.
Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
may 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 your battery or if your
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This may 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 GM dealer can prepare the
vehicle for inspection.
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Cruise Control Light
The cruise light comes on
whenever you set your
cruise control. See“Cruise
Control”underTurn
Signal/Multifunction Lever
on page 3-8.
Tow/Haul Mode Light
This light is displayed
when the tow/haul mode
has been activated.
For more information, seeTowing a Trailer on
page 4-61.
Fuel Gage
The fuel gage, when the ignition is on, tells you about
how much fuel you have left in your tank.
The gage willfirst 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. SeeDriver Information Center
(DIC) on page 3-53.
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 tofill 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 tofill the tank.
•The gage goes back to empty when you turn off the
ignition.
Low Fuel Warning Light
The light next to the fuel gage will come on briefly when
you are starting the engine.
This light comes on when the fuel tank is low on fuel.
To turn it off, add fuel to the fuel tank. SeeFuel on
page 5-4.
Driver Information Center (DIC)
The DIC display is located on the instrument panel
cluster above the steering wheel. The DIC can display
information such as the trip odometer, fuel economy and
personalization features.
A (Trip Information):This button will display the
odometer, personal trip odometer, business trip
odometer, hourmeter, annual log and the timer.
B (Fuel Information):This button will display the
current range, average fuel economy, instant fuel
economy and engine oil life.
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C (Personalization):This button will change personal
options available on your vehicle.
D (Select):This button resets certain functions and
turns off or acknowledges messages on the DIC.
If your vehicle is not equipped with the DIC steering
wheel buttons you will not have all of the features listed
above, and you will turn off, or acknowledge DIC
messages by using the trip odometer reset stem located
on the instrument panel cluster.
DIC Operation and Displays
The DIC comes on when the ignition is on. After a short
delay the DIC will display the current driver and the
information that was last displayed before the engine
was turned off.
If a problem is detected, a warning message will appear
on the display. Pressing the select button will
acknowledge any current warning or service messages.
The DIC has different modes which can be accessed
by pressing the four buttons on the DIC. These buttons
are trip information, fuel information, personalization
and select. The button functions are detailed in
the following.If your vehicle is not equipped with the DIC steering
wheel buttons not all of the features listed will be
available on your vehicle.
Trip Information Button
Use the trip information button to scroll through the
ODOMETER, PERSONAL TRIP ON/OFF, BUSINESS
TRIP ON/OFF, HOURMETER, ANNUAL LOG and
TIMER. If the personal trip and/or the business trip are
set to ON, you will also be able to scroll through
more messages. SeePersonal TripandBusiness Trip
next for more information.
If your vehicle is not equipped with the DIC steering
wheel buttons you can select the trip information
by pressing the trip odometer reset stem on the
instrument panel cluster.
Personal Trip
If the PERSONAL TRIP is on (turn it on or off by
pressing the select button) you will also be able to scroll
through the following:
•PERSONAL: XX MI—This shows the current
distance traveled since the last reset for the
personal trip odometer in either miles or kilometers.
•PERSONAL: XX.X GAL—This shows the amount
of fuel used for the personal trip.
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•PERSONAL: XX.X MPG—This shows the amount
of fuel used for the personal trip.
•PERSONAL: AVG MPH—This shows the vehicle’s
average speed for the personal trip.
•PERSONAL: % ANNUAL—This shows the ratio of
personal trip miles to annual miles as a percent.
You can reset the personal trip odometer by pressing
and holding the trip odometer reset stem.
Business Trip
If the BUSINESS TRIP is on (turn it on or off by
pressing the select button) you will also be able to scroll
through the following:
•BUSINESS: XX MI—This shows the current
distance traveled since the last reset for the
business trip odometer in either miles or kilometers.
•BUSINESS: XX.X MPG—This shows the amount
of fuel used for the business trip.
•BUSINESS: XX.X GAL—This shows the amount
of fuel used for the business trip.
•BUSINESS: AVG MPH—This shows the vehicle’s
average speed for the business trip.
•BUSINESS: % ANNUAL—This shows the ratio of
business trip miles to annual miles as a percent.
To reset the personal or business trip information, do the
following: press and hold select button for two seconds
while in one of the personal or business trip modes. This
will reset all of the information for the personal or
business trip, or if your vehicle does not have the DIC
steering wheel control buttons, press the reset stem on
the instrument panel cluster.
You can also reset the PERSONAL: XX MI, or
BUSINESS: XX MI, while they are displayed by pressing
the reset stem on the cluster. If you press and hold
the reset stem or select button for four seconds,
the display will show the distance traveled since the last
ignition cycle for the personal or business trip.
Odometer
Press the trip information button, or the trip odometer
reset step, until SEASON ODOMETER appears on
the display. This shows the total distance the vehicle has
been driven in either miles or kilometers. Pressing the
reset stem located on the instrument cluster with
the vehicle off will also display the season odometer.
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Hourmeter
Press the trip button to scroll to the hourmeter. The
hourmeter shows the total number of hours the engine
has run. Pressing the reset stem on the instrument
cluster will also display the hourmeter after the season
odometer is displayed.
Annual Log
Press the trip button, or the reset stem on the instrument
panel cluster, to scroll to the annual log. The annual
log shows the mileage accumulated since it was
last reset. To reset the annual log, press and hold the
select button, or the trip odometer reset stem for
approximately two seconds.
Timer
The DIC can be used as a stopwatch. Press the select
button, or the trip odometer reset stem, while TIMER
is displayed to start the timer. 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 roll
back to zero.To stop the counting of time, press the select button
briefly while TIMER is displayed.
To reset the timer to zero, press and hold the select
button, or the trip odometer reset stem, while TIMER is
displayed.
Fuel Information Button
Use the fuel information button to scroll through the
range, average fuel economy, instant fuel economy and
the GM Oil Life System™.
If your vehicle is not equipped with the DIC steering
wheel control buttons you will not be able to display the
fuel information.
Fuel Range
Press the fuel information button until RANGE appears
to display the remaining distance you can drive
without refueling. It’s based on fuel economy and the
fuel remaining in the tank. The display will show LOW if
the fuel level is low.
The fuel economy data used to determine fuel range is
an average of recent driving conditions. As your
driving conditions change, this data is gradually updated.
Fuel range cannot be reset.
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