service GMC YUKON DENALI 2005 Owner's Manual

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 awhile, 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 does not come on, have it repaired.
This light will also come on during a malfunction in
one of two ways:
Light Flashing— A misre condition has been
detected. A misre 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
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If the light stops ashing and remains on steady, see “If
the Light Is On Steady” following.
If the light continues to ash, 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
ashing, 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 5-8. 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, misring, 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 to x any
mechanical or electrical problems that may have
developed.
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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. SeeEngine Oil on page 5-14.
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be
covered by your warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
Security Light
This light will come on
briey when you turn the
key toward START.
The light will stay on until
the engine starts.
If the light ashes, the Passlock
®system has entered a
tamper mode. If the vehicle fails to start, seePasslock®
on page 2-19.
If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
®
system. Your vehicle will not be protected by Passlock®,
and you should see your dealer.
Also, seeContent Theft-Deterrent on page 2-17for
additional information regarding the security light.
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LEFT REAR DOOR AJAR
If the driver’s side rear door is not fully closed and the
vehicle is in a drive gear, this message will appear
on the display and you will hear a chime. Stop and turn
off the vehicle, check the door for obstacles and
close the door again. Check to see if the message still
appears on the DIC. Pressing any of the four DIC
buttons, if equipped, will clear the message from the
DIC display. If your vehicle is not equipped with the four
DIC buttons, pressing the trip odometer reset stem
will clear the message from the DIC display.
LOW COOLANT LEVEL
If your vehicle is equipped with low coolant level sensor,
this message will appear on the DIC if the engine coolant
level is low. Adding coolant will clear the message. See
Cooling System on page 5-30. Pressing any of the four
DIC buttons, if equipped, will acknowledge the message
and clear it from the DIC display. If your vehicle is not
equipped with the four DIC buttons, pressing the trip
odometer reset stem will acknowledge the message and
clear it from the DIC display.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
“Overheated Engine Protection Operating Mode”
in the Index for information on driving to a safe
place in an emergency.
OIL LIFE RESET
This message will appear on the display for about
10 seconds after resetting the change engine oil
message. See “Engine Oil Life System” underDIC
Operation and Displays on page 3-47andEngine Oil on
page 5-14for more information.
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 by your GM dealer. SeeEngine
Oil on page 5-14.
Notice:If you drive your vehicle while the engine
oil pressure is low, severe engine damage may
occur. If a low oil pressure warning appears on the
Driver Information Center (DIC), stop the vehicle
as soon as possible. Do not drive the vehicle until
the cause of the low oil pressure is corrected.
SeeEngine Oil on page 5-14for more information.
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PASSENGER DOOR AJAR
If the passenger’s door is not fully closed and the
vehicle is in a drive gear, this message will appear on
the display and you will hear a chime. Stop and turn off
the vehicle, check the door for obstacles and close
the door again. Check to see if the message still
appears on the DIC. Pressing any of the four DIC
buttons, if equipped, will clear the message from the DIC
display. If your vehicle is not equipped with the four
DIC buttons, pressing the trip odometer reset stem will
clear the message from the DIC display.
REAR ACCESS OPEN
If the liftgate is open while the ignition is in RUN, 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 any of the four DIC buttons,
if equipped, will clear the message from the DIC display.
If your vehicle is not equipped with the four DIC
buttons, pressing the trip odometer reset stem will clear
the message from the DIC display.
REDUCED ENGINE POWER
This message is displayed and you will hear a chime
when the cooling system temperature gets too hot and
the engine further enters the engine coolant protection
mode. SeeEngine Overheating on page 5-28for further
information.
REPLACE LIFTGATE FUSE
This message will be displayed if the liftgate lock
malfunctions and/or the liftgate fuse blows. For more
information on fuses, seeFuses and Circuit Breakers on
page 5-105. If the message returns after replacing the
fuse, see your GM dealer for service.
RIGHT REAR DOOR AJAR
If the passenger’s side rear door is not fully closed and
the vehicle is in a drive gear, this message will
appear on the display and you will hear a chime. Stop
and turn off the vehicle, check the door for obstacles and
close the door again. Check to see if the message
still appears on the DIC. Pressing any of the four DIC
buttons, if equipped, will clear the message from the DIC
display. If your vehicle is not equipped with the four
DIC buttons, pressing the trip odometer reset stem will
clear the message from the DIC display.
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SERVICE 4WD
If a problem occurs with the all-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. See your
GM dealer.
SERVICE AIR BAG
If there is a problem with the airbag system, this
message will be displayed on the DIC. Have your
GM dealer inspect the system for problems. SeeAirbag
Readiness Light on page 3-31andAirbag System on
page 1-70for more information. Pressing any of the four
DIC buttons, if equipped, will clear the message from
the DIC display. If your vehicle is not equipped with the
four DIC buttons, pressing the trip odometer reset
stem will clear the message from the DIC display.
SERVICE BRAKE SYSTEM
If a problem occurs with the brake 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 brake system needs service.
See your GM dealer.
SERVICE CHARGING SYSTEM
On some vehicles, if there is a problem with the battery
charging system, this message will appear on the
DIC. Under certain conditions, the charging system light
may also turn on in the instrument panel cluster. See
Charging System Light on page 3-33. The battery
will not be charging at an optimal rate and the vehicle
will lose the ability to enter the fuel economy mode. The
vehicle is safe to drive, however you should have the
electrical system checked by your GM dealer. Pressing
any of the four DIC buttons, if equipped, will clear
the message from the DIC display. If your vehicle is not
equipped with the four DIC buttons, pressing the trip
odometer reset stem will clear the message from
the DIC display.
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SERVICE RIDE CONTROL
If a problem occurs with the suspension system, this
message will appear on the DIC. If this message
appears, stop 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 suspension system needs
service. See your GM dealer.
SERVICE STABILITY
If you ever see the SERVICE STABILITY message, it
means there may be a problem with your StabiliTrak®
system. If you see this message, try to reset the system.
Stop; turn off the engine; then start the engine again.
If the SERVICE STABILITY message still comes
on, it means there is a problem. You should see your
GM dealer for service. The vehicle is safe to drive,
however, you do not have the benet of StabiliTrak
®,so
reduce your speed and drive accordingly.
SERVICE TIRE MONITOR
If your vehicle is equipped with the tire pressure monitor
system, this message will be displayed if any of the
tire monitor sensors have malfunctioned or if all the
tire monitor sensors have not been programmed
successfully. Pressing any of the four DIC buttons, if
equipped, will clear the message from the DIC display.
If your vehicle is not equipped with the four DIC
buttons, pressing the trip odometer reset stem will clear
the message from the DIC display. The message will
appear at each ignition cycle until the system is
serviced. See your GM dealer.
STABILITY SYS ACTIVE
You may see the STABILITY SYS ACTIVE message on
the DIC. It means that an advanced computer-controlled
system has come on to help your vehicle continue to
go in the direction in which you are steering. StabiliTrak
®
activates when the computer senses that your vehicle
is just starting to spin, as it might if you hit a patch of ice
or other slippery spot on the road. When the system
activates, you may hear a noise or feel a vibration in the
brake pedal. This is normal. When the STABILITY
SYS ACTIVE message is on, you should continue to
steer in the direction you want to go. The system
is designed to help you in bad weather or other difficult
driving situations by making the most of whatever
road conditions will permit.
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STABILITY SYS DISABLED
The STABILITY SYS DISABLED message will turn on
when you press the StabiliTrak®button, or when the
stability control has been automatically disabled. To limit
wheel spin and realize the full benets of the stability
enhancement system, you should normally leave
StabiliTrak
®on. However, you should turn StabiliTrak®off
if your vehicle gets stuck in sand, mud, ice or snow and
you want to “rock” your vehicle to attempt to free it, or if
you are driving in extreme off-road conditions and require
more wheel spin. SeeIf You Are Stuck: In Sand, Mud, Ice
or Snow on page 4-42. To turn the StabiliTrak
®system
back on, press the StabiliTrak®button again.
There are four conditions that can cause this message
to appear.
One condition is overheating, which could occur if
StabiliTrak®activates continuously for an extended
period of time.
The message will also be displayed if the brake
system warning light is on. SeeBrake System
Warning Light on page 3-34.
The message could be displayed if the stability
system takes longer than usual to complete its
diagnostic checks due to driving conditions.
Also, if an engine or vehicle related problem has
been detected, and the vehicle needs service,
the message will appear. See your GM dealer.
The message will turn off as soon as the conditions that
caused the message to be displayed are no longer
present.
TIGHTEN FUEL CAP
If the vehicle’s fuel cap is not tightened properly, this
message may appear along with the check engine light
on the instrument panel cluster. SeeMalfunction
Indicator Lamp on page 3-39. Reinstall the fuel cap
fully. SeeFilling Your Tank on page 5-8. 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 this light and message off.
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This system relies upon receiving specic 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 the radio is tuned to an RDS station, the station
name or 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™ Satellite Radio Service
XM™ is a satellite radio service that is based in the
48 contiguous United States. XM™ offers
100 coast-to-coast channels including music, news,
sports, talk, and children’s programming. XM™ provides
digital quality audio and text information that includes
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.
oVOLp(Volume):Turn this knob to increase or to
decrease the volume.
INFO (Information):Press this knob to switch the
display between the radio station frequency and
the time. When the ignition is off, press this knob to
display the time.
For RDS, press the INFO 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™ (if equipped), press the INFO knob while
in XM™ mode to retrieve four different categories
of information related to the current song or channel:
Artist, Song Title, Category or PTY, Channel
Number/Channel Name.
To change the default on the display, press the INFO
knob until you see the display you want, then hold
the knob until you hear a beep. The selected display will
now be the default.
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SCAN:Scan the stations within a PTY by performing
the following:
1. Press the TYPE button to activate program type
select mode. TYPE and the last selected PTY will
appear on the display.
2. Turn the TYPE knob or press and release the
TYPE button to select a PTY.
3. Once the desired PTY is displayed, press and
hold either the TYPE or the SCAN arrows for
two seconds, and the radio will begin scanning the
stations in the PTY.
4. Press either the TYPE or the SCAN arrows to stop
at a station.
BAND (Alternate Frequency):Alternate frequency
allows the radio to switch to a stronger station with the
same program type. To turn alternate frequency on,
press and hold BAND for two seconds. AF ON will
appear on the display. The radio may switch to stations
with a stronger frequency.
To turn alternate frequency off, press and hold BAND
again for two seconds. AF OFF will appear on the
display. The radio will not switch to other stations.
This function does not apply for XM™ Satellite
Radio Service.Setting Preset PTYs (RDS Only)
These buttons have factory PTY presets. Up to 12 PTYs
(six FM1 and six FM2), can be programmed on the
six numbered pushbuttons, by performing the
following steps:
1. Press BAND to select FM1 or FM2.
2. Press the TYPE button to activate program type
select mode. TYPE and the last selected PTY will
appear on the display.
3. Turn the TYPE knob or press and release the
TYPE button to select a PTY.
4. Press and hold one of the six numbered
pushbuttons until you hear a beep. Whenever that
numbered pushbutton is pressed, the PTY that
was set will return.
5. Repeat the steps for each pushbutton.
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