service GMC SIERRA DENALI 2003 Owner's Manual

Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition and emission
control systems.
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This system is called OBD I1 (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: Modifications 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.
Modifications 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 - A misfire condition has been
detected.
A misfire increases vehicle emissions
and may damage the emission control system on
your vehicle. Dealer or qualified service center
diagnosis and service may be required.
Light On Steady - An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center 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.
0 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 stops flashing and remains on steady, see “If
the Light
Is On Steady” following.
If the light continues to flash, 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 drive the vehicle
to your dealer or qualified service center for service.
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. See
Fi//ing 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.
Have you recently changed brands of fuel?
If
so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. 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,
have your dealer or qualified service center check
the vehicle. Your dealer has the proper test equipment
and diagnostic tools to
fix any mechanical or electrical
problems that may have developed.
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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, see your dealer or qualified service
center to prepare the vehicle for inspection.
Oil Pressure Gage
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United States Canada
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.
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A reading in the low pressure zone 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
DIC Warnings and Messages on
page 3-53
and ‘vgine Oil on page 5-13.
Don’t keep driving if the oil pressure is low. If
you do, your engine can become
so hot that it
catches fire. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice: Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
Cruise Control Light
The cruise light comes on
whenever you set your
cruise control. See “Cruise
Control” under
Turn
SignaVMultifunction Lever
on page 3-5.
Tow/HauI Mode Light
This light is displayed
when the tow/haul mode
has been activated.
For more information, see
Towing a Trailer on
page 4-5
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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.
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.
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CHANGE ENGINE OIL
This message is displayed when the engine oil needs to
be changed.
When you change the engine oil, be sure to reset the
CHANGE ENGINE
OIL message. See Engine Oil, When
to Change
under Engine Oil on page 5-13.
OIL LIFE RESET
This message will appear on the display for about 10
seconds after resetting the change engine oil message.
LOW COOLANT LEVEL
If the engine coolant level is low, this message will
appear on the DIC. Adding coolant will clear the
message.
ENGINE COOLANT HOT
If the cooling system temperature gets hot, this message
will appear in the DIC. Stop the vehicle and let the
engine idle in PARK (P) to allow the coolant to reach a
safe temperature. This message will clear when the
coolant temperature drops to safe operating
temperature.
ENGINE OVERHEATED
If the engine cooling system reaches unsafe
temperatures for operation, this message will appear in
the DIC and you will hear a chime. Stop and turn
off
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the vehicle as soon as it is safe to do so to avoid
severe damage. This message will clear when the
engine has cooled to a safe operating temperature.
OIL PRESSURE LOW
If low oil pressure levels occur, this message will be
displayed on the DIC and a chime will sound. Stop the
vehicle as soon as safely possible and do not operate
it until the cause of the low oil pressure has been
corrected. Check your oil as soon as possible and have
your vehicle serviced.
REDUCED ENGINE POWER
This message is displayed when the cooling system
temperature gets too hot and the engine further enters
the engine coolant protection mode.
See
Engine Overheating on page 5-27 for further
information.
BATTERY NOT CHARGING
if the battery is not charging during operation, this
message will appear on the DIC. Driving with this
problem could drain your battery. Have the electrical
system checked as soon as possible. Pressing the
select button will acknowledge this message and clear it
from the DIC display.

SERVICE AIRBAG
If there is a problem with the air bag system, this
message will be displayed on the
DIC. Have a qualified
technician inspect the system for problems. Pressing
the select button will acknowledge this message
and clear it from the
DIC display.
SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this
message will be displayed on the
DIC. If this message
appears, stop as soon as possible and turn
off the
vehicle. Restart the vehicle and check for the message
on the
DIC display. If the message is still displayed,
or appears again when you begin driving, the brake
system needs service.
SERVICE BRAKE BOOSTER
If your vehicle has vaccum assist power brakes, this
message will be displayed on the
DIC when there is a
problem with the Supplemental Brake Assist system.
If the message is displayed immediately after starting
the vehicle or the message appears while driving,
your Supplemental Brake Assist system needs service.
See
Brake System Warning Light on page 3-34.
Your brake system may not be working
properly if the SERVICE BRAKE BOOSTER
message is displayed.
If the brake system warning light is also on,
you should have the vehicle towed for service. See “Brake System Warning Light”
in the
Index.
If the brake system warning light
isn’t on, you
still have brakes, but the supplemental brake
assist system may not operate properly.
In the
event of a vacuum
loss, you may not have
vacuum power assist for braking. The brake pedal will
be harder to push and it will take
longer to stop.
If you continue to drive with
this message displayed it can lead to a crash.
Have the brake system serviced as soon as
possible.
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SERVICE 4WD
If a problem occurs with the four wheel drive system,
this message will appear on the DIC.
If this message
appears, stop as soon as possible and turn
off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed,
or appears again when you begin driving, the four wheel
drive system needs service.
SERVICE AIR SUSPENSION
If a problem occurs with the suspension system, this
message will appear
on the DIC. If this message
appears, stop as soon as possible and turn
off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed,
or appears again when you begin driving, the air
suspension system needs service.
TURN SIGNAL ON
If a turn signal is left on for 314 of a mile (1.2 km), this
message will appear on the display and you will
hear a chime. Move the turn signaVmultifunction lever to
the
off position. Pressing the select button will
acknowledge this message and clear it from the DIC
display.
CARGO LAMP ON
If the cargo lamp is on, this message will appear on the
DIC and you will hear a chime. Turn
off the vehicle
and check the liftgate. Restart the vehicle and check for
the message on the
DIC display. Pressing the select
button will acknowledge this message and clear it from
the DIC display.
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REDUCED BRAKE POWER
If your vehicle has vacuum assist power brakes, this
message will be displayed and you may notice that the
brake pedal is harder to push and it will take longer
to stop. You may also hear a motor running and feel a
slight vibration in the brake pedal or steering wheel
when you apply or release the brake pedal even
if your
foot is not on the brake pedal. This indicates that the
Supplemental Brake Assist system is working to
maintain braking power.
If you are braking lightly, you
may not notice any difference in the operation
of
your brakes.
This message may also be displayed for brief periods
if
you are driving at higher elevations and are pumping
your brakes or braking hard. The message may
clear after you’ve lifted your foot from the accelerator
pedal an allowed the vehicle to coast
in gear or after you
have driven down to a lower elevation. This is a
normal operation of your brake system and does not
require that the brake system be serviced. However,
if
the message does not clear, your brake system
needs service. While the message is displayed you will
notice that the brake pedal is harder to push and
it
will take longer to stop. See Brake System Warning
Light
on page 3-34.
Your brake system may not be working
properly if the REDUCED BRAKE POWER
message is displayed. If this message comes
on and stays on while driving, pull
off the road
and stop carefully. The brake pedal will be
harder to push and
it will take longer to stop.
If the message is no longer displayed after you
have pulled
off the road and stopped, you can
continue driving.
However, if the message is still displayed, or if
it comes on again when you are driving, there
is a problem with your brake system. If you
continue to drive with this message displayed
it can lead to an accident. You should have the
vehicle towed for service. Also, see Brake
System Warning Light in the Index.
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FUEL LEVEL LOW
If the fuel level is low, this message will appear on the
DIC and you will hear a chime. Refuel as soon as
possible. Pressing the select button will acknowledge
this message and clear it from the DIC display.
CHECK OIL LEVEL
If the oil level in the vehicle is low, this message will
appear on the DIC. Check and oil level and correct it as
necessary. You may need
to let the vehicle cool or
warm up and cycle the ignition to be sure this message
will clear. Once the problem is corrected, pressing
the select button will clear this message from the DIC
display.
CHECK WASHER FLUID
If the washer fluid level is low, this message will appear
on the DIC. Adding washer fluid will clear the message.
Pressing the select button will acknowledge this
message and clear it from the DIC display.
SERVICE 4 WHEEL STEER
If a problem occurs with the 4 wheel steer system, this
message will appear on the DIC. If this message
appears, stop as soon as possible and turn
off the
vehicle. Restart the vehicle and check for the message
on the DIC display.
If the message is still displayed,
or appears again when you begin driving, the four wheel
steer system needs service.
TRACTION ACTIVE
When the traction control system had detected that any
of the vehicle’s wheels are slipping, the traction
control system will activate and this message will appear
on the DIC. For more information see “Traction Assist”
in the Index.
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