
The 2003 GMC  Sierra Denali Owner  Manual a 
Seats  and  Restraint  Systems ........................... 1-1 
Front  Seats ............................................... 1-2 
Rear  Seats 
............................................... 1-7 
Safety  Belts 
.............................................. 1-8 
Child  Restraints 
....................................... 1-30 
Air  Bag  Systems 
...................................... 1-57 
Restraint  System  Check 
............................ 1-73 
Features  and  Controls 
..................................... 2-1 
Keys 
........................................................ 2-2 
Doors  and  Locks 
....................................... 2-6 
Windows 
................................................. 2-1 0 
Theft-Deterrent  Systems ............................ 2-1 3 
Starting  and Operating Your Vehicle ........... 2-15 
Mirrors 
.................................................... 2-28 
Onstar@  System 
...................................... 2-33 
HomeLink@  Transmitter 
............................. 2-35 
Storage  Areas 
......................................... 2-39 
Instrument  Panel 
............................................. 3-1 
Vehicle 
Personalization 
............................. 2-42 
Instrument  Panel  Overview 
.......................... 3-2 
Climate  Controls 
...................................... 3-1 8 
Warning  Lights,  Gages  and  Indicators 
......... 3-24 
Driver Information Center  (DIC) 
.................. 3-43 
Audio  System(s) 
....................................... 3-61  Driving  Your  Vehicle 
....................................... 4-1 
Your 
Driving, the  Road, and Your  Vehicle ..... 4-2 
Towing 
................................................... 4-45 
Service  and Appearance Care 
.......................... 5-1 
Service 
..................................................... 5-3 
Fuel 
......................................................... 5-5 
Checking  Things  Under  the  Hood 
............................................. 5-10 
All-Wheel  Drive 
........................................ 5-49 
Rear  Axle 
............................................... 5-50 
Front Axle 
............................................... 5-51 
Bulb  Replacement 
.................................... 5-52 
Windshield  Wiper Blade Replacement 
......... 5-60 
Tires 
...................................................... 5-61 
Appearance  Care 
..................................... 5-86 
Vehicle  Identification 
................................. 5-94 
Electrical  System 
...................................... 5-95 
Capacities  and Specifications 
................... 5-1 04 
Normal  Maintenance  Replacement  Parts 
.... 5-1 05 
Maintenance  Schedule 
..................................... 6-1 
Maintenance  Schedule 
................................ 6-2 
Customer Assistance  Information 
.................... 7-1 
Customer  Assistance  Information 
.................. 7-2 
Reporting Safety  Defects 
............................ 7-9 
Index 
................................................................. 1  

These are  some examples of vehicle  symbols you may find on your vehicle: 
POSSIBLE /r 
CAUTION 
INJURY 
PROTECT  EYES  BY 
SHIELDING 
CAUSTIC 
ACID  COULD  BATTERY 
CAUSE 
BURNS 
AVOID 
SPARKS 
OR 
FLAMES 
SPARK 
OR 
COULD  FLAME 
'\Ir8 
EXPLODE 
BAlTERY  LATCH  BOTH  LAP  AND 
SHOULDER  BELTS  TO 
PROTECT  OCCUPANT 
48: @ 
DO  NOT  TWIST  SAFm 
BELT  WHEN  AlTACHING 
FASTEN  SEAT 
BELTS 
MOVE  SEAT  FULLY 
\v! 
REARWARD* /g 
SECURE 
CHILD  SEAT 
PULL  BELT 
COMPLETELY 
THEN  SECURE  CHILD 
SEAT 
DO NOT  INSTALL 
A  REAR-FACING 
CHILD  RESTRAINT 
@o 
POSITION 8 
IN  THIS  SEATING 
DO  NOT  INSTALL 
A 
CHILD  RESTRAINT p? 
FORWARD-FACING  IN  THIS  SEATING  POSITION 
8 
DOOR  LOCK 
UNLOCK  SGHTING 
- MASTER SWITCH B- / ,  
SIGNALS @e 
TURN 
PARKING 
PC 
LAMPS 
RUNNING 
*:{io 
DAYTIME  LAMPS 
LAMPS 
#O 
ENGINE 
COOLANT 
cc. 
TEMP 
CHARGING  BAlTERY 
SYSTEM 
COOLANT 
ENGINE  OIL  PRESSURE 
W& 
ANTI-LOCK (@) 
BRAKES 
FE E] 
ACCESS 
COOLANT 
m-1 
ENGINE  FAN 
OWNERS  MANUAL 
SERVICE 
MANUAL 
V  

Q: 
A: 
If I’m  a  good  driver, and I never drive far from 
home,  why  should 
I wear safety  belts? 
You  may  be  an  excellent driver, but 
if you’re in an 
accident 
- even  one  that isn’t your fault - you  and 
your  passengers  can  be hurt. Being  a  good 
driver  doesn’t  protect  you  from things beyond your 
control,  such as bad  drivers. 
Most  accidents  occur  within 
25 miles (40 km)  of 
home.  And  the  greatest number of serious injuries 
and  deaths  occur  at  speeds  of  less than 
40 mph 
(65 km/h). 
Safety  belts are  for everyone. 
How to Wear  Safety  Belts  Properly 
This part is  only  for people of adult size. 
Be  aware  that  there are special things to  know about 
safety  belts and children.  And there are different 
rules  for  smaller  children and babies.  If  a child will  be 
riding  in your  vehicle,  see 
Older Children  on page 1-30 
or lnfants  and  Young  Children on page 1-32. Follow 
those  rules for  everyone’s  protection. 
First, you’ll  want  to  know  which  restraint systems  your 
vehicle  has. 
Driver Position 
This  part describes  the driver’s restraint system. 
Lap-Shoulder Belt 
The  driver  has  a lap-shoulder belt. Here’s  how to wear  it 
properly. 
1. Close  and lock the door. 
2. Adjust  the seat so you  can  sit  up  straight. To see 
how,  see  “Seats’’  in the  Index. 
We’ll  start  with  the  driver  position. 
1-13  

Section 2 Features  and  Controls 
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 
Rear  Doors 
................................................... 2-8 
Tailgate 
........................................................ 2-8 
Windows 
........................................................ 2-10 
Power  Windows 
............................................ 2-11 
Swing-Out  Windows 
...................................... 2-11 
Sun  Visors 
................................................... 2-12 
Theft-Deterrent  Systems 
.................................. 2.13 
Content  Theft-Deterrent 
................................. 2.13 
Passlock@ 
.................................................... 2.14 
Starting  and  Operating  Your  Vehicle 
................ 2.15 
New  Vehicle  Break-In 
.................................... 2.15 
Ignition Positions 
.......................................... 2.15 
Starting  Your  Engine 
..................................... 2.16 
Engine  Coolant  Heater 
.................................. 2.17 
Automatic  Transmission Operation 
................... 2.18 
All-Wheel  Drive 
............................................ 2-21 
Parking  Brake 
.............................................. 2-22 
Shifting 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 
OnStap,  Compass  and  Temperature 
Display 
.................................................... 2-28 
Outside  Power Mirrors 
................................... 2-31 
Outside  Power  Foldaway  Mirrors 
..................... 2-31 
Outside Automatic  Dimming Mirror 
.................. 2-31 
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 
................................... 2-42 
Memory  Seat 
............................................... 2-42 
2- 1  

Your vehicle  has  one 
double-sided key  for the 
ignition  and all door 
locks as well  as the spare 
tire hoist  lock, 
if equipped. 
If you  ever  lose  your  keys,  your dealer will be able to 
assist  you  with  obtaining replacements. 
Notice: Your  vehicle has a  number of features  that 
can  help  prevent  theft.  You  can have a lot 
of 
trouble  getting  into  your  vehicle  if  you  ever  lock 
your  keys  inside.  You  may even have to damage 
your  vehicle  to  get  in. 
So be sure  you have 
spare  keys. 
If  you  ever  do  get  locked out of your vehicle, call the 
GM Roadside  Assistance  Center. See Roadside 
Assistance  Program 
on page 7-5. If your vehicle  is 
equipped  with  the  Onstar@ system with an active  subscription 
and  you lock your  keys inside  the vehicle, 
OnStar@  may  be  able 
to send  a  command  to unlock 
your vehicle.  See 
OnStap System on page 2-33 
for  more information. 
Remote  Keyless  Entry  System 
Your keyless entry  system operates  on a radio 
frequency subject  to Federal  Communications 
Commission  (FCC)  Rules and with  Industry  Canada. 
This device complies  with Part 
15 of the  FCC  Rules. 
Operation  is subject  to  the following  two conditions: 
1. This device  may  not  cause  interference, and 
2. This device must accept  any interference received, 
including interference that  may  cause undesired 
operation  of the  device. 
This device complies  with 
RSS-210 of Industry  Canada. 
Operation  is subject 
to the following  two conditions: 
1. This device  may  not  cause  interference, and 
2. This device must accept  any interference received, 
including interference  that  may  cause undesired 
operation 
of the device. 
Changes  or  modifications 
to this system  by other  than 
an  authorized service facility could  void authorization  to 
use  this equipment. 
2-3  

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 is 
necessary.  See “Battery  Replacement”  under 
Remote Keyless  Entry  System Operation  on 
page 
2-4. 
qualified technician  for service. 
If you  are still having trouble,  see your dealer or  a 
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.  See 
DlC  Operation  and 
Displays  on  page 
3-43 for  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.  See 
DlC  Operation 
and  Displays  on  page 
3-43 for  more  information. 
Operating  the keyless  entry transmitter  may interact  with 
the theft-deterrent  system.  See 
Content  Theft-Deterrent 
on  page 
2- 13 and DlC  Operation  and Displays  on 
page 
3-43 for  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 flash  for  up to 
30 seconds.  This can 
be  turned  off by pressing  the  horn button again,  waiting 
for 
30 seconds,  or starting the  vehicle. 
2-4  

Doors and Locks 
Door Locks 
I 
To lock and unlock  your  vehicle,  do  one  of the  following: 
You can  use  the keyless  entry  system, 
use  your  key, or 
Unlocked  doors  can  be  dangerous. 
e 
e 
e Passengers - especially  children - can 
easily  open  the  doors  and  fall  out  of  a  moving  vehicle.  When  a  door 
is locked,  the 
handle  won’t  open 
it. You  increase  the 
chance  of  being  thrown  out  of  the  vehicle 
in a  crash  if  the  doors  aren’t  locked. So, 
wear  safety  belts  properly  and  lock  the 
doors  whenever  you  drive. 
Young  children  who  get  into  unlocked 
vehicles  may  be  unable  to  get  out. 
A child 
can  be  overcome  by  extreme  heat  and  can 
suffer  permanent  injuries  or  even  death 
from  heat  stroke.  Always  lock  your  vehicle 
whenever  you  leave 
it. 
Outsiders  can  easily  enter  through  an 
unlocked  door  when  you  slow  down  or 
stop  your  vehicle.  Locking  your  doors  can 
help  prevent 
this from  happening. 
e lock  the  door  from  the 
inside  by  sliding the 
manual  lock  lever 
rearward. 
To unlock  the 
door,  slide the  manual 
lock  lever  forward. 
2-6  

Power Door Locks 
If  your vehicle is  equipped 
with  power  door  locks, 
press the  raised side  of the 
switch, with the lock 
symbol,  on  either front 
door  to lock all the doors 
at  once.  Press the  recessed side 
of the switch with the  unlock 
symbol, to  unlock  all the doors  at once. 
The  power  door  locks will operate  at  any time even 
when  the ignition is 
off. 
Operating  the power  locks may interact with the 
theft-deterrent  system  (if equipped).  See 
Content 
Theft-Deterrent  on page 
2- 13. 
2-7