
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

Keys...............................................................2-2
Remote Keyless Entry System.........................2-3
Remote Keyless Entry System Operation...........2-4
Doors and Locks.............................................2-6
Door Locks....................................................2-6
Power Door Locks..........................................2-7
Programmable Automatic
Door Locks................................................2-7
Rear Doors...................................................2-9
Tailgate.......................................................2-10
Windows........................................................2-11
Power Windows............................................2-12
Swing-Out Windows......................................2-12
Sun Visors...................................................2-13
Theft-Deterrent Systems..................................2-13
Content Theft-Deterrent.................................2-13
Passlock
®....................................................2-15
Starting and Operating Your Vehicle................2-15
New Vehicle Break-In....................................2-15
Ignition Positions
..........................................2-16
Starting Your Engine
.....................................2-17
Engine Coolant Heater
..................................2-18
Automatic Transmission Operation
...................2-19
All-Wheel Drive
............................................2-21
Parking Brake
..............................................2-22Shifting Into Park (P).....................................2-23
Shifting Out of Park (P).................................2-25
Parking Over Things That Burn.......................2-26
Engine Exhaust............................................2-26
Running Your Engine While You Are Parked. . . .2-27
Mirrors...........................................................2-28
Automatic Dimming Rearview Mirror with
OnStar
®, Compass and Temperature
Display....................................................2-28
Outside Power Mirrors...................................2-31
Outside Power Foldaway Mirrors.....................2-31
Outside Automatic Dimming Mirror..................2-32
Outside Curb View Assist Mirrors....................2-32
Outside Convex Mirror...................................2-32
Outside Heated Mirrors..................................2-32
OnStar
®System.............................................2-33
HomeLink®Transmitter...................................2-35
Programming the HomeLink®Transmitter.........2-35
Storage Areas................................................2-39
Glove Box...................................................2-39
Cupholder(s)................................................2-39
Center Console Storage Area.........................2-39
Tonneau Cover............................................2-39
Vehicle Personalization...................................2-41
Memory Seat...............................................2-41
Section 2 Features and Controls
2-1
2003 - Sierra Denali

Sun Visors
To block out glare, you can swing down the top and
bottom visors. You can also swing the bottom visor from
side-to-side. The visors may also have an extension
that can be pulled out for additional glare protection.
Illuminated Visor Vanity Mirrors
Your vehicle may have this feature. If it does, pull the
sun visor down and lift the mirror cover to turn on
the lamps. There is a slide switch to adjust the intensity
of the lamps.
Theft-Deterrent Systems
Vehicle theft is big business, especially in some cities.
Although your vehicle has a number of theft-deterrent
features, we know that nothing we put on it can make it
impossible to steal. However, there are ways you
can help.
Content Theft-Deterrent
Your vehicle is equipped with a content theft-deterrent
alarm system.
With this system, the
security light on the cluster
will ash as you open
the door (if your ignition is
off), to let you know
that you are activating the
system.
This message reminds you to activate the theft-deterrent
system. Here’s how to do it:
1. Open the door.
2. Lock the door with the power door lock switch or
the remote keyless entry transmitter. The security
light should come on and ash. If you are using the
remote keyless entry transmitter, the door does
not need to be open.
3. Close all of the doors. The light will stop ashing and
stay solid.The security light should go off after
approximately 30 seconds. The alarm is not armed
until the security light goes off. If the delayed locking
feature is active, the alarm will not activate until all
doors are closed and the security light goes off.
2-13
2003 - Sierra Denali

Mirrors
Automatic Dimming Rearview Mirror
with OnStar
®, Compass and
Temperature Display
Your vehicle may have this feature. When on, an
electrochromic mirror automatically dims to the proper
level to minimize glare from lights behind you after dark.
The mirror also includes a duel display in the upper
right corner of the mirror face. The compass reading and
the outside temperature will both appear in the display
at the same time.
P(On/Off):This is the on/off button.
Temperature and Compass Display
Press the on/off button, located to the far left, brie yto
turn the comp/temp display on or off.
If the display reads CAL, you will need to calibrate the
compass. For more information on calibration, see
below.
To adjust between Fahrenheit and Celsius do the
following:
1. Press and hold the on/off button for approximately
four seconds until either a ashing°F, or°C
appears.
2. Press the button again to change the display to the
desired unit of measurement. After approximately
four seconds of inactivity, the new unit will be locked
in and the compass/temperature display will
return.
Electrochromic Mirror Operation
The electrochromic (self dimming) mirror function is
turned on automatically each time the ignition is started.
To operate the electrochromic mirror do the following:
1. Make sure the green indicator light, located to
the left of the on/off button, is lit. If it’s not, press
and hold the on/off button for approximately
six seconds until the green light comes on,
indicating that the mirror is in electrochromic
(self dimming) mode.
2-28
2003 - Sierra Denali

Outside Power Mirrors
If your vehicle is equipped
with outside power mirrors,
the controls are located
on the driver’s door
armrest.
Move the selector switch located above the control pad
to the left or right to choose the mirror you want to
adjust, then press the dots located on the four-way
control pad to adjust the mirror.
The mirrors include ground illumination lamps (puddle
lamps) in the base of the mirror. For more information on
these lamps, seePuddle LampsunderExterior Lamps
on page 3-11.
The mirrors also include a memory function which works
in conjunction with the memory seats. See“Memory
Seats”in the Index for more information.
Outside Power Foldaway Mirrors
If your vehicle is equipped with outside power foldaway
mirrors the mirrors can be folded in toward the body
of the vehicle.
To fold in the mirrors, move the upper selector switch,
located above the mirror control, to the middle position.
Press the right side of the mirror control to fold the
mirrors toward the body of the vehicle. The mirror glass
on one or both sides of the vehicle may automatically
adjust before the mirror folds inward. When the
mirror glass or mirror starts moving, you can release the
mirror control.
To return the mirrors and the mirror glass to their
normal position press the left side of the mirror control.
If the mirrors are manually folded, unfold and fold
them atleast twice using the mirror controls. Do not
unfold them manually. They may not stay in place
otherwise.
2-31
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.
2-32
2003 - Sierra Denali

To store your memory seat, mirrors and radio presets,
do the following:
1. Adjust the driver’s seat (including the seatback
recliner, lumbar, and side wing area), both of the
outside mirrors, and the radio station presets to your
preference.
2. Press and hold the 1 or 2 (for driver 1or 2) button
of the memory control for three seconds. A double
chime will sound to let you know that the position
has been stored.
To repeat the procedure for a second driver, follow the
preceding steps, but press the other numbered
memory control button.
Each time button 1 or 2 is pressed and released while
the vehicle is in PARK (P), a single chime will sound and
the memory position will be recalled.
If you use the unlock button on the remote keyless entry
transmitter to enter your vehicle, the preset driver’s
seat, mirror positions and the radio station presets will
be recalled if programmed to do so through the
Driver Information Center (DIC). The numbers on the
back of the transmitters, 1 or 2, correspond to the
numbers on the memory controls.
The seat and mirror positions can also be recalled when
placing the key in the ignition if programmed to do so
through the Driver Information Center (DIC).
To stop recall movement of the memory seat feature at
any time, press one of the memory buttons or power
seat controls.Easy Exit Seat
The controls for this memory function are located on the
driver’s door.
BThis button is used to program and recall the
desired driver’s seat position when exiting/entering the
vehicle. The seat position, can be personalized for
both driver 1 and driver 2.
To store the seat exit position for driver 1 or 2, do the
following:
1. Select the desired driver number by pressing and
releasing the 1 or 2 button. The seat will move to
the stored memory position.
2. Adjust the seat to the desired exit position.
3. Press and hold the exit button of the memory
control for three seconds. A double chime will sound
to let you know that the position has been stored
for the identi ed driver (1 or 2).
To use the seat exit position, do one of the following:
Press the exit button on the memory control.
Or, if this feature is enabled (active) in the DIC,
then removing the key from the ignition will
cause the seat to move to the exit position.
2-42
2003 - Sierra Denali

Rear Window Defogger
If your vehicle has this feature, the lines you see on the
rear window warm the glass. The rear window
defogger uses a warming grid to remove fog from the
rear window.
<(Rear):Press this button to turn the rear window
defogger on or off. An indicator light in the button
will come on to let you know that the rear window
defogger is activated.
The rear window defogger will turn off about 10 minutes
after the button is pressed. If you need additional
warming time, press the button again.
If your vehicle is equipped with heated mirrors this
button will activate them.
Notice:Don’t use a razor blade or something else
sharp on the inside of the rear window. If you
do, you could cut or damage the defogger and the
repairs would not be covered by your warranty.
Do not attach a temporary vehicle license, tape, a
decal or anything similar to the defogger grid.
Outlet Adjustment
Use the air outlets located in the center and on the side
of your instrument panel to direct the airflow.
Your vehicle has air outlets that allow you to adjust the
direction and amount of airflow inside the vehicle.
Move the louvers up or down. Use the thumbwheel next
to or underneath the outlet to close the louvers. For
the most efficient airflow and temperature control, keep
the outlet in the fully opened position.
Rear seat outlets can be used to adjust airflow toward
either seating area, thefloor or upward. Move the center
louvers up or down to direct the airflow.
3-23
2003 - Sierra Denali