
Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-2
Rear Seats
............................................... 1-6
Safety Belts
.............................................. 1-8
Child Restraints
.......................................1-28
Air Bag Systems
......................................1-49
Restraint System Check
............................1-59
Features and Controls..................................... 2-1
Keys
........................................................ 2-3
Doors and Locks
....................................... 2-8
Windows
.................................................2-14
Theft-Deterrent Systems
............................2-16
Starting and Operating Your Vehicle
...........2-18
Mirrors
....................................................2-34
OnStar
žSystem
......................................2-38
HomeLinkžTransmitter
.............................2-39
Storage Areas
.........................................2-43
Sunroof
..................................................2-50
Vehicle Personalization
.............................2-50
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-4
Climate Controls
......................................3-21
Warning Lights, Gages and Indicators
.........3-35
Driver Information Center (DIC)
..................3-51Audio System(s)
.......................................3-64
Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-44
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-4
Checking Things Under the Hood
...............5-10
Rear Axle
...............................................5-47
Four-Wheel Drive
.....................................5-48
Bulb Replacement
....................................5-50
Windshield Wiper Blade Replacement
.........5-51
Tires
......................................................5-54
Appearance Care
.....................................5-79
Vehicle Identi®cation
.................................5-87
Electrical System
......................................5-88
Capacities and Speci®cations
...................5-100
Normal Maintenance Replacement Parts
....5-102
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 Chevrolet TrailBlazerM

Rear Seats
Rear Seat Operation
Your vehicle may have a folding rear seat which lets
you fold the seatbacks down for more cargo space.
Pull up on the loop located where the seat cushion
meets the seatback to fold the seat cushion up and out
of the way. This will allow the seatback to fold ¯at
and increase the cargo area.The rear seatback
levers are located on the
outboard side of the
rear seatbacks.
Pull the seatback toward you as you lift up on the lever.
The head restraint will automatically fold out of the
way when the seatback is folded down.
To raise the seatbacks, lift up the seatbacks and push
on them until they lock into the upright position.
Push and pull on the seatbacks to make sure that they
are latched securely. Then fold the bottom seat
cushion back into place.
1-6

To return the head restraint to the upright position,
reach behind the seat and pull the restraint up until it
locks into place. Push and pull on the head restraint to
make sure that it is latched securely.
Rear Seats (TrailBlazer EXT)
The second row seat is a 65/35 split seat which may be
folded and tumbled. Use this feature for gaining
access to the third row seats.To fold and tumble the second row seat(s), do the
following:
1. Push the head restraints fully down.
2. Fold the seatback ¯at on the seat by pulling up on
the front part of the fold and tumble lever. The lever
is located on the outboard side of the seat
(indicated as 1 on the handle side cover).
3. Release the rear set of seat hooks from the ¯oor
pins by pulling up on the rear part of the lever
(indicated as 2 on the handle side cover). This
enables the seat to be tumbled forward.
Returning the Seats to an Upright Position
To return the seat(s) to the upright position, do the
following:
1. Pull the bottom of the seat release lever towards
the front of the vehicle to release the seat. The
lever is located at the bottom of the seat cushion on
the outboard side of each second row seat.
2. Return the seat to the ¯oor pins by rotating the seat
down to reengage the seat hooks.
3. Try to raise the seat to check that it is locked down.
4. Pull the seat back up to return it to the upright
position.
1-7

Q:What if a child is wearing a lap-shoulder belt,
but the child is so small that the shoulder belt
is very close to the child's face or neck?
A:If the child is sitting in a seat next to a window,
move the child toward the center of the vehicle.
If the child is sitting in the center rear seat
passenger position, move the child toward the
safety belt buckle. In either case, be sure that the
shoulder belt still is on the child's shoulder, so
that in a crash the child's upper body would have
the restraint the belts provide.
If the child is sitting in a rear seat outside position,
see
Rear Safety Belt Comfort Guides for Children
and Small Adults on page 1-24
.
1-30

{CAUTION:
The body structure of a young child is quite
unlike that of an adult or older child, for whom
the safety belts are designed. A young child's
hip bones are still so small that the vehicle's
regular safety belt may not remain low on the
hip bones, as it should. Instead, it may settle
up around the child's abdomen. In a crash, the
belt would apply force on a body area that's
unprotected by any bony structure. This alone
could cause serious or fatal injuries. Young
children always should be secured in
appropriate child restraints.
Child Restraint Systems
An infant car bed (A), a special bed made for use in a
motor vehicle, is an infant restraint system designed
to restrain or position a child on a continuous ¯at
surface. Make sure that the infant's head rests toward
the center of the vehicle.
1-34

What Makes an Air Bag In¯ate?
In an impact of sufficient severity, the air bag sensing
system detects that the vehicle is in a crash. For
both frontal and side impact air bags, the sensing
system triggers a release of gas from the in¯ator, which
in¯ates the air bag. The in¯ator, the air bag and
related hardware are all part of the air bag modules.
Frontal air bag modules are located inside the steering
wheel and instrument panel. For vehicles with side
impact air bags, the air bag modules are located in the
seatback closest to the driver's and/or right front
passenger's door.
How Does an Air Bag Restrain?
In moderate to severe frontal or near frontal collisions,
even belted occupants can contact the steering wheel or
the instrument panel. In moderate to severe side
collisions, even belted occupants can contact the inside
of the vehicle. The air bag supplements the protection
provided by safety belts. Air bags distribute the force of
the impact more evenly over the occupant's upper
body, stopping the occupant more gradually. But the
frontal air bags would not help you in many types
of collisions, including rollovers, rear impacts, and many
side impacts, primarily because an occupant's motion
is not toward the air bag. Side impact air bags would not
help you in many types of collisions, including frontal
or near frontal collisions, rollovers, and rear impacts,
primarily because an occupant's motion is not toward
those air bags. Air bags should never be regarded
as anything more than a supplement to safety belts, and
then only in moderate to severe frontal or near-frontal
collisions for the driver's and right front passenger's
frontal air bags, and only in moderate to severe
side collisions for vehicles with a driver's and right front
passenger's side impact air bag.
1-56

Programmable Automatic
Door Locks
Your vehicle is equipped with an automatic lock/unlock
feature which enables you to program your vehicle's
power door locks. You can program this feature through
the Driver Information Center (DIC), or by the following
method.
Programmable Locking Feature
The following is the list of available programming
options:
Mode 1:All doors lock when the transmission is shifted
into gear.
Mode 2:All doors lock when the vehicle speed is
greater than 8 mph (13 km/h).
Mode 3:No automatic door locking.
The automatic door locks were pre-programmed at the
factory to lock all the doors when the transmission
is shifted into gear. The following instructions detail how
to program your door locks differently than the factory
setting. Choose one of the three programming
options listed above before entering the program mode.To enter the program mode, do the following:
1. Begin with the ignition off. Then pull the turn
signal/multifunction lever toward you and hold
it there while you perform the next step.
2. Turn the key to RUN and LOCK twice. Then, with
the key in LOCK, release the turn signal/multifunction
lever. Once you do this, you will hear the lock switch
lock and unlock, the horn will chirp twice, and a
30 second program timer will begin.
3. You are now ready to program the automatic door
locks. Select one of the three programming options
listed above, and press the lock side of the power
door lock switch to cycle through the lock options.
You will have 30 seconds to begin programming.
If you exceed the 30 second limit, the locks will
automatically lock and unlock and the horn will chirp
twice to indicate that you have left the program
mode. If this occurs, repeat the procedure beginning
with Step 1 to re-enter the programming mode.
You can exit the program mode any time by turning the
ignition to RUN. The locks will automatically lock and
unlock and the horn will chirp twice to indicate that you
are leaving the program mode. If the lock/unlock
switches are not pressed while in the programming
mode, the current auto lock/unlock setting will not
be modi®ed.
See your dealer for more information.
2-10

Programmable Unlocking Feature
The following is the list of available programming
options:
Mode 1:Driver's door unlocks when the transmission
is shifted into PARK (P).
Mode 2:All doors unlock when the transmission is
shifted into PARK (P).
Mode 3:All doors unlock when the key is removed
from the ignition.
Mode 4:No automatic door unlock.
The automatic door locks were pre-programmed at the
factory to unlock the driver's door once the transmission
is shifted to PARK (P). The following instructions detail
how to program your door locks differently than the
factory setting. Choose one of the four programming
options listed above before entering the program mode.
To enter the program mode you need to do the
following:
1. Begin with the ignition off. Then pull the turn
signal/multifunction lever toward you and hold
it there while you perform the next step.2. Turn the key to RUN and LOCK twice. Then, with
the key in LOCK, release the turn signal/multifunction
lever. Once you do this, you will hear the lock switch
lock and unlock, the horn will chirp twice, and a
30 second program timer will begin.
3. You are now ready to program the automatic door
locks. Select one of the four programming options
listed above, and press the unlock side of the power
door lock switch to cycle through the unlocking
options. You will have 30 seconds to begin
programming. If you exceed the 30 second limit,
the locks will automatically lock and unlock and the
horn will chirp twice to indicate that you have left
the program mode. If this occurs, repeat the
procedure beginning with Step 1 to re-enter the
programming mode.
You can exit the program mode any time by turning the
ignition to RUN. The locks will automatically lock and
unlock and the horn will chirp twice to indicate that you
are leaving the program mode. If the lock/unlock
switches are not pressed while in the programming
mode, the current auto lock/unlock setting will not
be modi®ed.
See your dealer for more information.
2-11