ignition GMC YUKON 2003 Service Manual

This light should come on briefly when you turn the
ignition key to RUN. If it doesn’t come on then, have it
fixed so it will be ready to warn you if there’sa
problem.
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 4-54.
{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. United States
Canada
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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 3-43.
Traction Off Light
If you have the Traction
Assist System, this light
should come on briefly
when you turn the ignition
to RUN.
If the light doesn’t come on then, the system may
require service; have itfixed so it will be there to warn
you if the system is turned off.If the light stays on, or comes on when you’re driving,
there may be a problem with your Traction Assist
System and your vehicle may need service. When this
light is on, the system will not limit wheel spin. Adjust
your driving accordingly.
The traction off light may come on for the following
reasons:
•If you turn the system off by pressing the TAS
on/off button located to the left of the steering wheel,
the light will come on and stay on. To turn the
system back on, press the button again; the light
should go off.
•If you move the shift lever to FIRST (1), the light
will come on and stay on to indicate that the
traction system is off. This is normal operation. To
turn the system back on, move the shift lever
back to a position other than FIRST (1); the light
should go off. SeeTraction Assist System (TAS) on
page 4-10.
•The light will come on and stay on if the TAS
automatic engagement feature has been turned off.
To turn the system on, press the TAS off/on
button; the light should go off. To turn the automatic
engagement feature back on, seeTraction Assist
System (TAS) on page 4-10.
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When your ignition is on, the gage shows the
temperature of the transmissionfluid. The normal
operating range is from 100°F (38°C) to about
265°F (130°C).
At approximately 265°F (130°C), the message center
will display a TRANSMISSION HOT message and
the transmission will enter a transmission protection
mode. When the transmission enters the protection
mode, you may notice a change in the transmission
shifting patterns. The transmission will return to normal
shifting patterns when the transmissionfluid temperature
falls below 260°F (127°C).
SeeDriver Information Center (DIC) on page 3-53for
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.
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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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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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Automatic Locking
Press the personalization button until AUTOMATIC
LOCKING appears in the display. To select your
personalization for automatic locking, press the select
button while AUTOMATIC LOCKING is displayed on the
DIC. Pressing the select button will scroll through the
following choices:
LOCK DOORS MANUALLY:The doors will not be
locked automatically.
LOCK DOORS WITH SPEED:The doors will lock
when the vehicle speed is above 8 mph (13 km/h) for
three seconds.
LOCK DOORS OUT OF PARK (default):The doors
will lock when the vehicle is shifted out of PARK (P).
Choose one of the three options and press the
personalization button while it is displayed on the DIC to
select it and move on to the next feature. For more
information on automatic door locks seeProgrammable
Automatic Doors Locks.
Automatic Unlocking
Press the personalization button until AUTOMATIC
UNLOCKING appears in the display. To select
your personalization for automatic unlocking, press the
select button while AUTOMATIC UNLOCKING is
displayed on the DIC. Pressing the select button will
scroll through the following choices:
UNLOCK ALL IN PARK (default):All of the doors will
unlock when the vehicle is shifted into PARK (P).
UNLOCK ALL AT KEY OUT:All of the doors will
unlock when the key is taken out of the ignition.
UNLOCK DOORS MANUALLY:The doors will not be
unlocked automatically.
UNLOCK DRIVER IN PARK:The driver’s door will be
unlocked when the vehicle is shifted in PARK (P).
Choose one of the four options and press the
personalization button while it is displayed on the DIC to
select it and move on to the next feature. For more
information on automatic door locks seeProgrammable
Automatic Door Locks.
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