
Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-2
Rear Seats
............................................... 1-6
Safety Belts
.............................................. 1-7
Child Restraints
.......................................1-29
Air Bag Systems
......................................1-55
Restraint System Check
............................1-71
Features and Controls..................................... 2-1
Keys
........................................................ 2-2
Doors and Locks
....................................... 2-6
Windows
.................................................2-11
Theft-Deterrent Systems
............................2-13
Starting and Operating Your Vehicle
...........2-15
Mirrors
....................................................2-28
OnStar
®System
......................................2-33
HomeLink®Transmitter
.............................2-35
Storage Areas
.........................................2-39
Vehicle Personalization
.............................2-41
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-2
Climate Controls
......................................3-18
Warning Lights, Gages and Indicators
.........3-24
Driver Information Center (DIC)
..................3-42
Audio System(s)
.......................................3-56Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-46
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-4
Checking Things Under
the Hood
.............................................5-10
All-Wheel Drive
........................................5-45
Rear Axle
...............................................5-46
Front Axle
...............................................5-47
Bulb Replacement
....................................5-48
Windshield Wiper Blade Replacement
.........5-56
Tires
......................................................5-56
Appearance Care
.....................................5-82
Vehicle Identi cation
.................................5-90
Electrical System
......................................5-91
Capacities and Speci cations
.....................5-99
Normal Maintenance Replacement Parts
....5-100
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance Information.................... 7-1
Customer Assistance Information
.................. 7-2
Reporting Safety Defects
............................ 7-8
Index................................................................ 1
2003 GMC Sierra Denali Owner ManualM
2003 - Sierra Denali Owner Manual

At times you may notice a decrease in range.
This is normal for any remote keyless entry system.
If the transmitter does not work or if you have to stand
closer to your vehicle for the transmitter to work,
try this:
Check the distance. You may be too far from your
vehicle. You may need to stand closer during
rainy or snowy weather.
Check the location. Other vehicles or objects may
be blocking the signal. Take a few steps to the
left or right, hold the transmitter higher, and
try again.
Check to determine if battery replacement or
resynchronization is necessary. See“Battery
Replacement”and‘‘Resynchronization’’under
Remote Keyless Entry System Operation on
page 2-4.
If you are still having trouble, see your dealer or a
quali ed technician for service.
Remote Keyless Entry System
Operation
You can lock and unlock your doors from about 3 feet
(1 m) up to 100 feet (30 m) away using the remote
keyless entry transmitter supplied with your vehicle.
UNLOCK:Pressing this button once will unlock
the driver’s door. The interior lamps will come on.
Pressing UNLOCK again within three seconds will cause
the remaining doors to unlock.
You can choose different feedback options for each
press of the UNLOCK button. SeeDIC Operation and
Displays on page 3-42for more information.
LOCK:Pressing this button once will lock all of the
doors. You can choose different feedback options
for each press of the LOCK button. SeeDIC Operation
and Displays on page 3-42for more information.
Operating the keyless entry transmitter may interact with
the theft-deterrent system. SeeContent Theft-Deterrent
on page 2-13andDIC Operation and Displays on
page 3-42for more information.
Remote Alarm
When the horn symbol on the keyless entry transmitter
is pressed, the horn will sound and the headlamps
and taillamps will ash for up to 30 seconds. This can
be turned off by pressing the horn button again, waiting
for 30 seconds, or starting the vehicle.
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2003 - Sierra Denali

Once the system is armed, if a door is opened without
the key or the remote keyless entry transmitter, the
alarm will go off. Depending on how you have
programmed the alarm in the secondary information
center, the horn may sound, the headlamps may ash
or both the headlamps and the horn will activate.
Remember, the theft-deterrent system won’t activate if
you lock the doors with a key or use the manual
door lock. It activates only if you use a power door lock
switch with the door open, or with the remote keyless
entry transmitter. You should also remember that
you can start your vehicle with the correct ignition key if
the alarm has been set off.
Here’s how to avoid setting off the alarm by accident:
If you don’t want to activate the theft-deterrent
system, the vehicle should be locked with the door
key after the doors are closed.
Always unlock a door with a key, or use the remote
keyless entry transmitter. Unlocking a door any
other way will set off the alarm if the system
has been armed.
If you set off the alarm by accident, unlock any door
with the key. You can also turn off the alarm by pressing
UNLOCK on the remote keyless entry transmitter or
by placing the key in the ignition and turning it to
START.
Testing the Alarm
The alarm can be tested by following these steps:
1. From inside the vehicle, lower the driver’s window
and open the driver’s door.
2. Activate the system by locking the doors with the
power door lock switch while the door is open, or
with the remote keyless entry transmitter.
3. Get out of the vehicle, close the door and wait for
the security message to go out.
4. Then reach in through the window, unlock the door
with the manual door lock and open the door. This
should set off the alarm.
If the alarm does not sound and the headlamps do not
ash, you may have the feature turned off. SeeDIC
Operation and Displays on page 3-42for more
information.
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2003 - Sierra Denali

Outside Automatic Dimming Mirror
The driver’s outside mirror will adjust for the glare of any
headlamps behind you. This feature is controlled by
the on and off settings on the electrochromic mirror.
See“Electrochromic Mirror Operation”underAutomatic
Dimming Rearview Mirror with OnStar
®, Compass
and Temperature Display on page 2-28.
Outside Curb View Assist Mirrors
If your vehicle has the optional memory package
you may have this feature.
The vehicle’s mirrors are capable of performing the curb
view assist mirror function. This feature will cause the
passenger’s and/or driver’s mirror to tilt to a preselected
position when the vehicle is in REVERSE (R). This
feature may be useful in allowing you to view the curb
when you are parallel parking. When the vehicle is
shifted out of REVERSE (R) and a short delay
has occurred, the passenger’s and/or driver’s mirror will
return to its original position.
To change the preselected tilt position, adjust the
mirrors to the desired position while the vehicle is in
REVERSE (R). When the vehicle is shifted out of
REVERSE (R), this new position is saved in memory as
the tilt position.
You may be able to enabled/disable this feature through
the Driver Information Center. SeeDriver Information
Center (DIC) on page 3-42.
Outside Convex Mirror
Your passenger’s side mirror is convex. A convex
mirror’s surface is curved so you can see more from the
driver’s seat.
{CAUTION:
A convex mirror can make things (like other
vehicles) look farther away than they really are.
If you cut too sharply into the right lane, you
could hit a vehicle on your right. Check your
inside mirror or glance over your shoulder
before changing lanes.
Outside Heated Mirrors
The outside rearview mirrors with this option have a
defrost mode.
To turn on the defrost feature, press the rear window
defogger button. See“Rear Window Defogger”
underDual Automatic Climate Control System on
page 3-18for further information.
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2003 - Sierra Denali

Instrument Panel Overview...............................3-2
Hazard Warning Flashers................................3-4
Other Warning Devices...................................3-4
Horn .............................................................3-5
Tilt Wheel.....................................................3-5
Turn Signal/Multifunction Lever.........................3-5
Exterior Lamps.............................................3-11
Interior Lamps..............................................3-15
Accessory Power Outlets...............................3-16
Ashtrays and Cigarette Lighter........................3-17
Climate Controls............................................3-18
Dual Automatic Climate Control System...........3-18
Warning Lights, Gages and Indicators.............3-24
Instrument Panel Cluster................................3-25
Speedometer and Odometer...........................3-26
Tachometer.................................................3-26
Safety Belt Reminder Light.............................3-27
Air Bag Readiness Light................................3-27
Air Bag Off Light..........................................3-28
Passenger Air Bag Status Indicator.................3-31
Battery Warning Light....................................3-33
Voltmeter Gage............................................3-33
Brake System Warning Light..........................3-34
Anti-Lock Brake System Warning Light.............3-35
Engine Coolant Temperature Gage..................3-36Transmission Temperature Gage.....................3-36
Malfunction Indicator Lamp.............................3-37
Oil Pressure Gage........................................3-40
Cruise Control Light......................................3-40
Tow/Haul Mode Light....................................3-41
Fuel Gage...................................................3-41
Low Fuel Warning Light.................................3-41
Driver Information Center (DIC).......................3-42
DIC Operation and Displays...........................3-42
DIC Warnings and Messages.........................3-51
Audio System(s).............................................3-56
Setting the Time...........................................3-57
Radio with Cassette and CD..........................3-57
Navigation/Radio System...............................3-70
Rear Seat Audio (RSA).................................3-71
CD Changer................................................3-73
Theft-Deterrent Feature..................................3-75
Audio Steering Wheel Controls.......................3-76
Understanding Radio Reception......................3-76
Care of Your Cassette Tape Player.................3-77
Care of Your CDs.........................................3-78
Care of Your CD Player................................3-78
Fixed Mast Antenna......................................3-78
XM™ Satellite Radio Antenna System
(United States Only)..................................3-78
Section 3 Instrument Panel
3-1
2003 - Sierra Denali

Automatic Headlamp System
When it is dark enough outside, your automatic
headlamp system will turn on your headlamps at the
normal brightness along with other lamps such as
the taillamps, sidemarker, parking lamps and the
instrument panel lights. The radio lights will also be dim.
Your vehicle is equipped with a headlamp off delay,
which will keep the headlamps on for a short time after
the ignition is turned off. For more information see
DIC Operation and Displays on page 3-42.
Your vehicle has a light sensor located on the top of the
instrument panel in the defroster grille. Be sure it is
not covered, or the system will be on whenever
the ignition is on.
The system may also turn on your headlamps when
driving through a parking garage, heavy overcast
weather or a tunnel. This is normal.
There is a delay in the transition between the daytime
and nighttime operation of the Daytime Running
Lamps (DRL) and the automatic headlamp systems so
that driving under bridges or bright overhead street
lights does not affect the system. The DRL and
automatic headlamp system will only be affected when
the light sensor sees a change in lighting lasting
longer than the delay.If you start your vehicle in a dark garage, the automatic
headlamp system will come on immediately. Once
you leave the garage, it will take approximately
one minute for the automatic headlamp system to
change to DRL if it is bright enough outside. During that
delay, your instrument panel cluster may not be as
bright as usual. Make sure your instrument panel
brightness control is in the full bright position. See
“Instrument Panel Brightness Control”underInterior
Lamps on page 3-15.
To idle your vehicle with the automatic headlamp
system off, turn the control to the off position.
You may be able to turn off your automatic headlamp
system. See Daytime Running Lamps (DRL) later in this
section for more information.
Your headlamps will also stay on after you exit the
vehicle. You can program this feature using the Driver
Information Center. SeeDriver Information Center (DIC)
on page 3-42
As with any vehicle, you should turn on the regular
headlamps if you need them.
3-12
2003 - Sierra Denali

Operation Tips
•
Keep the hood and front air inlets free of ice, snow,
or any other obstruction (such as leaves). The
heater and defroster will work far better, reducing
the chance of fogging the inside of your windows.
•Keep the air path under the front seats clear
of objects. This helps air to circulate throughout your
vehicle.
•Adding outside equipment to the front of your
vehicle, such as hood-air deflectors, etc., may affect
the performance of the heating and air conditioning
system. Check with your dealer before adding
equipment to the outside of your vehicle.
Warning Lights, Gages and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention to
your warning lights and gages could also save you
or others from injury.Warning lights come on when there may be or is a
problem with one of your vehicle’s functions. As you will
see in the details on the next few pages, some
warning lights come on briefly when you start the
engine just to let you know they’re working. If you are
familiar with this section, you should not be alarmed
when this happens.
Gages can indicate when there may be or is a problem
with one of your vehicle’s functions. Often gages
and warning lights work together to let you know when
there’s a problem with your vehicle.
When one of the warning lights comes on and stays on
when you are driving, or when one of the gages
shows there may be a problem, check the section that
tells you what to do about it. Please follow this
manual’s advice. Waiting to do repairs can be
costly–and even dangerous. So please get to know
your warning lights and gages. They’re a big help.
Your vehicle also has a driver information system that
works along with the warning lights and gages. See
Driver Information Center (DIC) on page 3-42.
3-24
2003 - Sierra Denali

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.
3-37
2003 - Sierra Denali