service GMC SIERRA 2003 Owner's Guide

If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the
floor. It may take longer to stop. If the light is still on,
have the vehicle towed for service. SeeTowing
Your Vehicle on page 4-46.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light is
on. Driving with the brake system warning light
on can lead to an accident. If the light is still
on after you’ve pulled off the road and stopped
carefully, have the vehicle towed for service.
Anti-Lock Brake System Warning
Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay on for
several seconds.
That’s normal. If the light doesn’t come on then, have it
fixed so it will be ready to warn you if there is a
problem.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. You will also hear a
chime sound when the light is on steady. If the regular
brake system warning light isn’t on, you still have
brakes, but you don’t have anti-lock brakes. If the
regular brake system warning light is also on you don’t
have anti-lock brakes and there’s a problem with
your regular brakes. In addition to both lights, you will
also hear a chime sound on thefirst occurrence of
a problem and each time the vehicle is shut off and then
restarted. SeeBrake System Warning Light on
page 3-34.
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SeeDriver Information Center (DIC) on page 3-42for
further information.
If the transmissionfluid reaches temperatures of
approximately 275°F (135°C) or greater, the Driver
Information Center will display a TRANS HOT IDLE
ENG warning message. Pull the vehicle off the roadway
when it is safe to do so. Set the parking brake, place
the transmission in PARK (P) and allow the engine
to idle until the transmission temperature falls below
260°F (127°C). If the transmission continues to operate
above 265°F (130°C), contact your nearest dealer or
the GM Roadside Assistance Center. SeeRoadside
Assistance Program on page 7-5.
Notice:If you keep driving your vehicle with the
transmission temperature gage above the normal
operating range, you can damage the transmission.
This could lead to costly repairs that may not be
covered under your warranty.
The following situations can cause the transmission to
operate at higher temperatures:
•Towing a trailer
•Hot outside air temperatures
•Hauling a large or heavy load
•Low transmissionfluid level
•High transmissionfluid level
•Restricted airflow to the radiator and the auxiliary
transmission oil cooler (if equipped).A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures
on a frequent basis, seeScheduled Maintenance
on page 6-5for the proper transmission maintenance
intervals.
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.
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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.
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
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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.
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. SeeDIC Warnings and Messages on
page 3-51andEngine Oil on page 5-13.
{CAUTION:
Don’t keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catchesre. 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”underTurn
Signal/Multifunction Lever
on page 3-5. United States
Canada
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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. SeeEngine Oil, When
to ChangeunderEngine 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 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.
SeeEngine Overheating on page 5-26for 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.
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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.
SeeBrake System Warning Light on page 3-34.
{CAUTION:
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 3/4 of a mile (1.2 km), this
message will appear on the display and you will
hear a chime. Move the turn signal/multifunction 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.
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 washerfluid level is low, this message will appear
on the DIC. Adding washerfluid will clear the message.
Pressing the select button will acknowledge this
message and clear it from the DIC display.
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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.
TRANSMISSION HOT
If the transmissionfluid temperature becomes high, the
message center will display this message.
When the transmission enters the protection mode, you
may notice a change in the transmission shifting
patterns. When the transmissionfluid temperature
returns to normal, the display will turn off and the
transmission shifting patterns will return to normal.Notice:If you keep driving your vehicle with the
transmission TRANS FLUID HOT message
displayed, you can damage the transmission. This
could lead to costly repairs that may not be covered
under your warranty.
The following situations can cause the transmission to
operate at higher temperatures:
•Towing a trailer
•Hot outside air temperatures
•Hauling a large or heavy load
•Low transmissionfluid level
•High transmissionfluid level
•Restricted airflow to the radiator and the auxiliary
transmission oil cooler.
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures
on a frequent basis, seeScheduled Maintenance
on page 6-5for the proper transmission maintenance
intervals.
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This system relies upon receiving specific information
from these stations and will only work when the
information is available. In rare cases, a radio station
may broadcast incorrect information that will cause
the radio features to work improperly. If this happens,
contact the radio station.
While you are tuned to an RDS station, the station name
or the call letters will appear on the display instead of the
frequency. RDS stations may also provide the time of
day, a program type (PTY) for current programming and
the name of the program being broadcast.
XM™Radio Satellite Service
(USA Only)
XM™is a continental U.S. based satellite radio service
that offers 100 coast to coast channels including
music, news, sports, talk and children’s programming.
XM™provides digital quality audio and text information,
including song title and artist name. A service fee is
required in order to receive the XM™service. For more
information, contact XM™at www.xmradio.com or
call 1-800-852-XMXM (9696).
Playing the Radio
PWR (Power):Press this knob to turn the system on
and off.
VOL (Volume):Turn this knob to increase or to
decrease volume.AUTO VOL (Automatic Volume):Your vehicle is
equipped with Bose AudioPilot
®noise compensation
technology. AudioPilot monitors the level of noise in the
vehicle and automatically increases or decreases the
level of the audio to keep your audio above the noise.
To use this feature press the AUTO VOL button
until AVOL ON appears on the display. This feature
works best at lower volume settings where background
noise may be louder than the audio. At high volume
settings, where the audio is much louder than the
background noise, there will be no change in the audio
level. To turn automatic volume off, press this button
until AVOL OFF appears on the display.
DISP (Display):Push this knob to switch the display
between radio station frequency and time. Time display
is available with the ignition turned off.
For RDS, push this knob to change what appears on
the display while using RDS. The display options
are station name, RDS station frequency, PTY and the
name of the program (if available).
For XM™(USA only, if your radio is equipped with
XM™Satellite Radio Service), push this knob while in
XM mode to retrieve various pieces of information
related to the current song or channel. By pressing and
releasing this knob, you may retrieve four different
categories of information: Artist, Song Title, Category or
PTY, Channel Number/Channel Name.
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