ECU CHEVROLET TRAIL BLAZER 2003 1.G Service Manual

Notice:Don't let anyone tell you that underin¯ation
or overin¯ation is all right. It's not. If your tires
don't have enough air (underin¯ation), you can get
the following:
·Too much ¯exing
·Too much heat
·Tire overloading
·Bad wear
·Bad handling
·Bad fuel economy
If your tires have too much air (overin¯ation), you
can get the following:
·Unusual wear
·Bad handling
·Rough ride
·Needless damage from road hazards
When to Check
Check your tires once a month or more.
Also, check the tire pressure of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can't tell if your tires are properly in¯ated
simply by looking at them. Radial tires may look
properly in¯ated even when they're underin¯ated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and
moisture.
Tire Inspection and Rotation
Tires should be rotated every 7,500 miles (12 500 km).
Any time you notice unusual wear, rotate your tires
as soon as possible and check wheel alignment. Also
check for damaged tires or wheels. See
When It Is Time
for New Tires on page 5-57andWheel Replacement
on page 5-61for more information.
Make sure the spare tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If it moves,
use the wheel wrench to tighten the cable. See
Changing a Flat Tire on page 5-64.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The ®rst rotation
is the most important. See ªPart A: Scheduled
Maintenance Services,º in Section 6, for scheduled
rotation intervals.
5-55

Follow this diagram to store the underbody-mounted
spare.
A. Wheel Wrench
B. Hoist Shaft
C. Extension(s)
D. Retainer
E. Spare or Flat Tire
(Valve Stem
Pointed Up)
1. Put the tire on the ground at the rear of the vehicle,
with the valve stem pointed up and to the rear.
2. Pull the retainer through the wheel.
3. Put the socket end of the extension, on an angle,
through the hole in the rear bumper and into the
hoist shaft.
4. Raise the tire fully against the underside of the
vehicle. Continue turning the wheel wrench
clockwise until you hear two clicks or feel it skip
twice. This indicates that the tire is secure and the
cable is tight. The spare tire hoist cannot be
overtightened.5. Make sure the tire is stored securely. Push, pull
and then try to turn the tire. If the tire moves, use
the wheel wrench and socket end of the extension
to tighten the cable.
Return the jack, wheel wrench and wheel blocks
to the proper location in the vehicle. Roll up
the instruction label and return it to the slot in the
tool kit.
5-77

At Least Twice a Year
Restraint System Check
Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors and anchorages
are working properly. Look for any other loose or
damaged safety belt system parts. If you see anything
that might keep a safety belt system from doing its
job, have it repaired. Have any torn or frayed safety belts
replaced.
Also look for any opened or broken air bag coverings,
and have them repaired or replaced. (The air bag
system does not need regular maintenance.)
Wiper Blade Check
Inspect wiper blades for wear or cracking. Replace
blade inserts that appear worn or damaged or that
streak or miss areas of the windshield. Also see
Cleaning the Outside of Your Vehicle on page 5-82.
Spare Tire Check
At least twice a year, after the monthly in¯ation check of
the spare tire determines that the spare is in¯ated to
the correct tire in¯ation pressure, make sure that
the spare tire is stored securely. Push, pull, and then try
to rotate or turn the tire. If it moves, use the wheel
wrench/ratchet to tighten the cable. See
Changing a Flat
Tire on page 5-64.
Weatherstrip Lubrication
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather more frequent application may be
required. See
Part D: Recommended Fluids and
Lubricants on page 6-18.
Automatic Transmission Check
Check the transmission ¯uid level; add if needed. SeeAutomatic Transmission Fluid on page 5-22. A ¯uid loss
may indicate a problem. Check the system and repair
if needed.
6-12

Checking Brake Fluid......................................5-39
Checking Coolant............................................5-25
Checking Engine Oil........................................5-16
Checking Things Under the Hood......................5-10
Checking Your Restraint Systems......................1-59
Chemical Paint Spotting...................................5-85
Child Restraints..............................................1-34
Child Restraint Systems...............................1-34
Infants and Young Children...........................1-31
Lower Anchorages and Top Tethers for
Children (LATCH System)..........................1-40
Older Children.............................................1-28
Securing a Child Restraint Designed for the
LATCH System........................................1-42
Securing a Child Restraint in a Rear Outside
Seat Position...........................................1-43
Securing a Child Restraint in the Center
Seat Position...........................................1-46
Securing a Child Restraint in the Right
Front Seat Position...................................1-46
Top Strap...................................................1-38
Top Strap Anchor Location............................1-39
Where to Put the Restraint...........................1-37
Chime Level Adjustment.................................3-108
Cigarette Lighter.............................................3-20
Cleaning Aluminum Wheels..............................5-84
Cleaning Exterior Lamps/Lenses.......................5-83
Cleaning Fabric/Carpet....................................5-79
Cleaning Glass Surfaces..................................5-81
Cleaning Interior Plastic Components.................5-81Cleaning Leather............................................5-81
Cleaning the Top of the Instrument Panel...........5-81
Cleaning the Windshield, Backglass and
Wiper Blades..............................................5-84
Cleaning Tires................................................5-84
Cleaning Vinyl................................................5-81
Cleaning........................................................5-79
Inside of Your Vehicle..................................5-79
Outside of Your Vehicle................................5-82
Underbody Maintenance...............................5-85
Video Screen............................................3-108
Weatherstrips..............................................5-82
Climate Control System...................................3-34
Climate Controls Personalization....................3-34
Dual Automatic............................................3-24
Dual..........................................................3-21
Rear..........................................................3-30
Steering Wheel Controls...............................3-34
Compact Disc Messages.................3-71, 3-81, 3-92
Compass Calibration.......................................2-35
Compass Operation.........................................2-34
Compass Variance..........................................2-35
Content Theft-Deferrent....................................2-16
Control of a Vehicle.......................................... 4-5
Convenience Net............................................2-49
Coolant.........................................................3-42
Engine Temperature Gage............................3-42
Heater, Engine............................................2-21
Cooling System..............................................5-29
Cruise Control Light........................................3-48
3

Cruise Control................................................3-12
Current and Past Model Order Forms................7-10
Customer Assistance Information........................ 7-7
Courtesy Transportation.................................. 7-7
Customer Assistance for Text
Telephone (TTY) Users............................... 7-4
Customer Assistance Offices........................... 7-4
Customer Satisfaction Procedure..................... 7-2
GM Mobility Program for Persons with
Disabilities................................................ 7-5
Reporting Safety Defects to General Motors...... 7-9
Reporting Safety Defects to the Canadian
Government.............................................. 7-9
Reporting Safety Defects to the United
States Government.................................... 7-8
Roadside Assistance Program......................... 7-5
Service Publications Ordering Information......... 7-9
D
Daytime Running Lamps (DRL).........................3-17
Defensive Driving............................................. 4-2
Defogging and Defrosting.........................3-22, 3-28
Delayed Locking............................................... 2-9
Dinghy Towing................................................4-45
Doing Your Own Service Work........................... 5-3
Dolly Towing..................................................4-47
Dome Lamp Override......................................3-18
Dome Lamps.................................................3-19Door............................................................... 2-9
Delayed Locking........................................... 2-9
Locks.......................................................... 2-8
Power Door Locks......................................... 2-9
Programmable Automatic Door Locks.............2-10
Rear Door Security Locks.............................2-12
DRIVER DOOR AJAR.....................................3-63
Driver Information Center (DIC).........................3-51
DIC Operation and Displays..........................3-52
DIC Warnings and Messages........................3-61
Driver............................................................1-14
Position, Safety Belt.....................................1-14
Driving Across an Incline..................................4-25
Driving Downhill..............................................4-23
Driving in Mud, Sand, Snow or Ice....................4-27
Driving in Water..............................................4-28
Driving On Grades..........................................4-58
Driving on Off-Road Hills.................................4-19
Driving on Snow or Ice....................................4-38
Driving Through Deep Standing Water...............4-32
Driving Through Flowing Water.........................4-32
Driving Uphill..................................................4-21
Driving with a Trailer.......................................4-56
Driving..........................................................4-29
At Night.....................................................4-29
City...........................................................4-33
Defensive..................................................... 4-2
Drunken....................................................... 4-2
Freeway.....................................................4-34
Hill and Mountain Roads..............................4-36
4

Instrument Panel Brightness.............................3-18
Instrument Panel.............................................3-36
Cluster.......................................................3-36
Overview..................................................... 3-4
Interior Lamps................................................3-18
J
Jump Starting.................................................5-42
K
Key Lock Cylinders Service..............................6-13
Keyless Entry System....................................... 2-5
Keys............................................................... 2-3
L
Lamps On Reminder.......................................3-16
Lamps...........................................................3-15
Exterior......................................................3-15
Interior.......................................................3-18
Lap-Shoulder Belt...................................1-14, 1-22
LATCH System...............................................1-40
Child Restraints...........................................1-40
Securing a Child Restraint Designed for the
LATCH System........................................1-42LATCH System (cont.)
Leaving Your Vehicle With the Engine
Running.....................................................2-30
Leaving Your Vehicle.......................................2-12
LEFT REAR DOOR AJAR................................3-63
Liftgate Rack System......................................2-47
Table.........................................................2-47
Liftgate Release..............................................2-13
Liftgate/Liftglass..............................................2-13
Liftglass/Liftgate..............................................2-13
Lighted Visor Vanity Mirror...............................2-16
Light.............................................................3-38
Air Bag Readiness.......................................3-38
Anti-Lock Brake System Warning...................3-42
Brake System Warning.................................3-41
Change Engine Oil......................................3-47
Charging System.........................................3-39
Check Gages Warning.................................3-49
Cruise Control.............................................3-48
Gate Ajar...................................................3-50
Low Fuel Warning.......................................3-51
Malfunction Indicator....................................3-43
Reduced Engine Power................................3-48
Safety Belt Reminder...................................3-38
Security.....................................................3-47
Service Four-Wheel-Drive Warning Light.........3-49
Loading Your Vehicle for Off-Road Driving..........4-16
Loading Your Vehicle.......................................4-48
Locking Rear Axle...........................................4-10
Lockout Protection..........................................2-12
8

Locks............................................................. 2-9
Delayed Locking........................................... 2-9
Door........................................................... 2-8
Leaving Your Vehicle....................................2-12
Lockout Protection.......................................2-12
Power Door.................................................. 2-9
Programmable Automatic Door Locks.............2-10
Rear Door Security Locks.............................2-12
Loss of Control...............................................4-14
Low Fuel Warning Light...................................3-51
Luggage Carrier..............................................2-47
Lumbar........................................................... 1-3
Manual Controls............................................ 1-3
Power Controls............................................. 1-3
M
Maintenance, Normal Replacement Parts..........5-102
Maintenance Schedule.....................................6-11
At Each Fuel Fill.........................................6-11
At Least Once a Month................................6-11
At Least Once a Year..................................6-13
At Least Twice a Year..................................6-12
Brake System Inspection..............................6-17
Engine Cooling System Inspection.................6-16
Exhaust System Inspection...........................6-16
Fuel System Inspection................................6-16
How This Section is Organized....................... 6-3
Introduction.................................................. 6-2Maintenance Schedule (cont.)
Maintenance Requirements............................. 6-2
Part A - Scheduled Maintenance Services......... 6-4
Part B - Owner Checks and Services.............6-11
Part C - Periodic MaintenanceInspections......6-16
Part D - Recommended Fluids and
Lubricants...............................................6-18
Part E - Maintenance Record........................6-20
Scheduled Maintenance................................. 6-5
Steering, Suspension and Front Drive Axle
Boot and Seal Inspection..........................6-16
Transfer Case and Front Axle
(Four-Wheel Drive) Inspection....................6-17
Using Your................................................... 6-4
Your Vehicle and the Environment................... 6-2
Maintenance When Trailer Towing.....................4-59
Making Turns.................................................4-57
Malfunction Indicator Light................................3-43
Manual Lumbar Controls.................................... 1-3
Manual Seats................................................... 1-2
Matching Transmitter(s) to Your Vehicle............... 2-6
Memory Seat.................................................2-50
Message.......................................................3-61
DIC Warnings and Messages........................3-61
Mexico, Central America and Caribbean Islands/
Countries (Except Puerto Rico and U.S. Virgin
Islands) ± Customer Assistance....................... 7-4
Mirror Operation.............................................2-34
Mirrors..........................................................2-34
9

Rear Compartment Storage Panel/Cover............2-45
Rear Door Security Locks................................2-12
Rear Floor Storage Lid....................................2-48
Rear Safety Belt Comfort Guides......................1-24
Rear Seat Audio (RSA)..................................3-104
Rear Seat Entertainment System.......................3-93
Rear Seat Operation......................................... 1-6
Rear Seat Passenger Positions.........................1-21
Rear Seat Passengers, Safety Belts..................1-21
Rear Seats (TrailBlazer EXT)............................. 1-7
Rear Underseat Fuse Block..............................5-95
Rear Window Defogger............................3-23, 3-28
Rearview Mirror, Automatic Dimming with
OnStar
žand Compass.................................2-34
Reclining Seatbacks.......................................... 1-4
Recreational Vehicle Towing.............................4-44
Reduced Engine Power Light............................3-48
Remote Control..............................................3-98
Remote Keyless Entry System, Operation............ 2-6
Remote Keyless Entry System............................ 2-5
Removing the Flat Tire and Installing the
Spare Tire..................................................5-71
Removing the Spare Tire and Tools...................5-65
Replacement Bulbs.........................................5-51
Replacing Brake System Parts..........................5-41
Replacing Restraint System Parts After
a Crash.....................................................1-60
Reporting Safety Defects................................... 7-9
Canadian Government................................... 7-9
General Motors............................................. 7-9Reporting Safety Defects (cont.)
United States Government.............................. 7-8
Reprogramming a Single HomeLink
žButton.......2-42
Resetting Defaults...........................................2-43
Restraint System Check...................................6-12
Checking Your Restraint Systems...................1-59
Replacing Restraint System Parts After
a Crash..................................................1-60
Restraint Systems...........................................1-59
Checking....................................................1-59
Replacing Parts...........................................1-60
Retained Accessory Power (RAP)......................2-19
RFA # BATTERY LOW....................................3-63
Right Front Passenger Position, Safety Belts......1-21
RIGHT REAR DOOR AJAR..............................3-63
Roadside......................................................... 7-5
Assistance Program....................................... 7-5
Rocking Your Vehicle To Get It Out...................4-42
Running Your Engine While You Are Parked.......2-32
S
Safety Belt.....................................................3-38
Reminder Light............................................3-38
Safety Belts...................................................5-82
Care of......................................................5-82
Driver Position............................................1-14
How to Wear Safety Belts Properly................1-14
Questions and Answers About Safety Belts.....1-13
12

Safety Belts (cont.)
Rear Safety Belt Comfort Guides for Children
and Small Adults......................................1-24
Rear Seat Passengers.................................1-21
Right Front Passenger Position......................1-21
Safety Belt Extender....................................1-27
Safety Belt Use During Pregnancy.................1-20
Safety Belts Are for Everyone......................... 1-8
Safety Chains.................................................4-55
Safety Warnings and Symbols.............................. iii
Scanning the Terrain.......................................4-18
Scheduled Maintenance..................................... 6-5
Seat............................................................... 1-5
Head Restraints............................................ 1-5
Seats.............................................................. 1-3
Heated Seats............................................... 1-3
Manual Lumbar............................................. 1-3
Manual........................................................ 1-2
Memory.....................................................2-50
Power Lumbar.............................................. 1-3
Power Seats................................................. 1-2
Rear Seat Operation...................................... 1-6
Reclining Seatbacks...................................... 1-4
Securing a Child Restraint................................1-46
Center Seat Position....................................1-46
Designed for the LATCH System...................1-42
Rear Outside Seat Position...........................1-43
Right Front Seat Position..............................1-46
Security Light.................................................3-47
Select...........................................................3-60SERVICE AIR BAG.........................................3-61
SERVICE BRAKE SYSTEM.............................3-62
Service Bulletins.............................................7-10
Service Engine Soon Light in the United States
or Check Engine Light in Canada..................3-43
Service Manuals............................................... 7-9
Service........................................................... 5-3
Adding Equipment to the Outside of Your
Vehicle..................................................... 5-4
Doing Your Own Work................................... 5-3
Engine Soon Light.......................................3-43
Four-Wheel-Drive Warning Light.....................3-49
Publications Ordering Information..................... 7-9
Setting Preset PTYs........................................3-86
Setting Preset Stations....................3-66, 3-73, 3-83
Setting the Time.............................................3-64
Setting the Tone (Bass/Treble)..........3-67, 3-74, 3-84
Sheet Metal Damage.......................................5-84
Shifting Into Park (P).......................................2-29
Shifting Out of Park (P)...................................2-31
Skidding........................................................4-14
Snow Plow....................................................4-50
Some Other Rainy Weather Tips.......................4-32
Spare Tire Check............................................6-12
Special Fabric Cleaning Problems.....................5-80
Speci®cations, Capacities...............................5-100
Speedometer..................................................3-37
Stalling on an Incline.......................................4-26
Starter Switch Check.......................................6-13
Starting Your Engine.......................................2-20
13