
Coolant
Engine Temperature Gage............................3-29
Heater, Engine............................................2-24
Cooling.........................................................3-18
Cooling System..............................................5-30
Crew Cab
®....................................................1-46
Cruise Control.................................................. 3-8
Current and Past Model Order Forms................7-10
Customer Assistance Information
Courtesy Transportation.................................. 7-7
Customer Assistance for Text Telephone (TTY)
Users....................................................... 7-3
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..................................3-12
Defensive Driving............................................. 4-2
Defogging and Defrosting.................................3-19Dinghy Towing................................................4-43
Directing the Airflow ........................................3-17
Doing Your Own Service Work........................... 5-3
Dolly Towing..................................................4-44
Dome Lamp ...................................................3-15
Door
Locks.......................................................... 2-8
Power Door Locks......................................... 2-9
Programmable Automatic Door Locks............... 2-9
Rear Door Security Locks.............................2-11
Third Door..................................................2-12
Driver
Position, Safety Belt.....................................1-16
Driver Information Center (DIC).........................2-46
Driving
At Night.....................................................4-27
City ...........................................................4-31
Defensive..................................................... 4-2
Drunken....................................................... 4-2
Freeway.....................................................4-32
Hill and Mountain Roads..............................4-34
In Rain and on Wet Roads...........................4-28
Winter........................................................4-36
Driving Across an Incline..................................4-22
Driving Downhill..............................................4-21
Driving in Mud, Sand, Snow or Ice....................4-25
Driving in Water..............................................4-26
Driving On Grades
..........................................4-59
Driving on Off-Road Hills
.................................4-18
4
2003 - Sonoma OM

Driving on Snow or Ice....................................4-37
Driving Through Deep Standing Water...............4-30
Driving Through Flowing Water.........................4-30
Driving Uphill..................................................4-19
Driving with a Trailer.......................................4-57
E
Electrical System
Add-On Equipment......................................5-88
Fuses and Circuit Breakers...........................5-89
Headlamps.................................................5-88
Power Windows and Other Power Options......5-88
Windshield Wiper Fuses...............................5-88
Electronic Transfer Case..................................2-30
Emissions Inspection and Maintenance
Programs...................................................3-32
Engine
Air Cleaner/Filter.........................................5-18
Battery.......................................................5-42
Check and Service Engine Soon Light............3-29
Compartment Overview................................5-10
Coolant......................................................5-25
Coolant Heater............................................2-24
Coolant Temperature Gage...........................3-29
Cooling System Inspection............................6-31
Exhaust.....................................................2-37
Fan Noise..................................................5-36Engine (cont.)
Oil .............................................................5-13
Overheating................................................5-28
Starting......................................................2-22
Engine Compartment Fuse Block......................5-91
Engine Coolant Level Check.............................6-26
Engine Oil Additives........................................5-16
Engine Oil Level Check...................................6-26
Entry Lighting.................................................3-14
Environmental Concerns..................................4-15
Exit Lighting...................................................3-14
Express Down Window....................................2-15
Extended Cab (Jump Seat)..............................1-48
Extender, Safety Belt.......................................1-29
Exterior Lamps...............................................3-10
F
Fabric/Carpet.................................................5-79
Filter
Engine Air Cleaner......................................5-18
Finding a PTY Station.....................3-43, 3-50, 3-60
Finding a Station....................3-38, 3-40, 3-48, 3-57
Finish Care....................................................5-83
Finish Damage...............................................5-85
Five-Speed....................................................2-28
Fixed Mast Antenna........................................3-69
Flash-To-Pass Feature....................................... 3-6
5
2003 - Sonoma OM

Headlamps (cont.)
Halogen Bulbs............................................5-50
One-Piece Front Turn Signal Lamps...............5-52
Two-Piece Front Turn Signal Lamps...............5-53
Heated Seats................................................... 1-5
Heating.........................................................3-18
Highway Hypnosis...........................................4-34
Hill and Mountain Roads..................................4-34
Hitches..........................................................4-56
Hood
Checking Things Under.................................. 5-8
Release....................................................... 5-9
Horn ............................................................... 3-4
How to Add Coolant to the Coolant
Recovery Tank............................................5-32
How to Add Coolant to the Radiator..................5-34
How to Add Fluid....................................5-22, 5-24
How to Check................................5-20, 5-23, 5-59
How to Check and Add Fluid
............................5-25
How to Check Lubricant
..........................5-47, 5-49
How to Check Power Steering Fluid
..................5-37
How to Inspect the Engine Air Cleaner/Filter
.......5-19
How to Use This Manual
...................................... ii
How to Wear Safety Belts Properly
...................1-15
Hydraulic Clutch
.............................................5-24
Hydraulic Clutch System Check
........................6-27
Hydroplaning
..................................................4-30I
If No Steam Is Coming From Your Engine..........5-29
If Steam Is Coming From Your Engine...............5-28
If the Light Is Flashing.....................................3-30
If the Light Is On Steady.................................3-31
If You Are Stuck in Sand, Mud, Ice or Snow.......4-40
If You Do Decide To Pull A Trailer.....................4-52
If You’re Caught in a Blizzard...........................4-38
Ignition Positions.............................................2-20
Ignition Transmission Lock Check......................6-29
Infants and Young Children, Restraints...............1-32
Inflation–Tire Pressure...................................5-58
Inspection
Brake System.............................................6-32
Engine Cooling System................................6-31
Exhaust System..........................................6-31
Fuel System...............................................6-31
Part C - Periodic Maintenance.......................6-31
Steering, Suspension and Front Drive
Axle Boot and Seal..................................6-31
Throttle System...........................................6-32
Transfer Case and Front Axle
(Four-Wheel Drive)...................................6-32
Installing a Garage Door Opener.......................2-43
Instrument Panel
Cluster.......................................................3-21
Overview..................................................... 3-2
7
2003 - Sonoma OM

Instrument Panel Brightness.............................3-14
Instrument Panel Fuse Block............................5-89
Interior Lamps................................................3-14
Interior Plastic Components..............................5-81
J
Jump Seat.....................................................1-10
Jump Starting.................................................5-43
K
Key Lock Cylinders Service..............................6-28
Key Release Button........................................2-21
Keyless Entry System....................................... 2-4
Keys............................................................... 2-3
L
Lamps
Exterior......................................................3-10
Interior.......................................................3-14
Lamps On Reminder.......................................3-12
Lap Belt................................................1-23, 1-25
Lap-Shoulder Belt...........................................1-16LATCH System
Child Restraints
...........................................1-44
Securing a Child Restraint Designed for the
LATCH System
........................................1-46
Latches, Seatback
............................................ 1-8
Leather
.........................................................5-81
Leaving Your Vehicle
.......................................2-11
Leaving Your Vehicle With the Engine Running
. . . 2-34
Light
Air Bag Off
.................................................3-24
Air Bag Readiness
.......................................3-24
Anti-Lock Brake System Warning
...................3-28
Brake System Warning
.................................3-27
Charging System
.........................................3-26
Check Gages Warning
.................................3-34
Low Fuel Warning
.......................................3-35
Malfunction Indicator
....................................3-29
Safety Belt Reminder
...................................3-23
Security
.....................................................3-33
Service Four-Wheel-Drive Warning Light
.........3-34
Up-Shift
.....................................................3-27
Loading Your Vehicle
.......................................4-46
Loading Your Vehicle for Off-Road Driving
..........4-14
Locking Rear Axle
............................................ 4-7
Lockout Protection
..........................................2-11
8
2003 - Sonoma OM

Parking
Brake........................................................2-32
Over Things That Burn.................................2-36
Parking Brake and Automatic Transmission
Park (P) Mechanism Check...........................6-30
Parking on Hills..............................................4-59
Parking Your Vehicle.......................................2-36
Part A - Scheduled Maintenance Services............ 6-4
Part B - Owner Checks and Services................6-26
Part C - Periodic Maintenance Inspections..........6-31
PartD-Recommended Fluids and Lubricants....6-33
PartE-Maintenance Record...........................6-35
Passing.................................................4-10, 4-58
Passlock
®......................................................2-19
Payload.........................................................4-48
Pickup Conversion to Chassis Cab....................4-50
Plan Ahead When Possible................................ 7-7
Playing a Cassette Tape..................................3-52
Playing a Compact Disc..................3-45, 3-54, 3-62
Playing a Specific Loaded
Compact Disc
.............................................3-63
Playing the Radio
...................3-37, 3-40, 3-47, 3-56
Power
Accessory Outlets
........................................3-15
Door Locks
.................................................. 2-9
Electrical System
.........................................5-88
Lumbar Controls
........................................... 1-5
Seat
............................................................ 1-4Power (cont.)
Steering Fluid.............................................5-37
Windows....................................................2-15
Power Steering................................................ 4-8
Programmable Automatic Door Locks.................. 2-9
Q
Questions and Answers About Safety Belts.........1-15
R
Radiator Pressure Cap....................................5-27
Radio Messages.............................3-39, 3-45, 3-52
Radios..........................................................3-36
AM-FM Radio.............................................3-37
Care of Your Cassette Tape Player................3-68
Care of Your CD Player...............................3-69
Care of Your CDs ........................................3-69
Radio with Cassette and CD.........................3-47
Radio with CD............................................3-40
Radio with Six-Disc CD................................3-56
Setting the Time for Radios with Radio
Data Systems (RDS)................................3-37
Setting the Time for Radios without Radio
Data Systems (RDS)................................3-36
Theft-Deterrent............................................3-67
Understanding Reception..............................3-67
RDS Messages..............................3-43, 3-51, 3-61
11
2003 - Sonoma OM

Rear Axle......................................................5-47
Locking........................................................ 4-7
Rear Door Security Locks................................2-11
Rear Seat Operation......................................... 1-9
Rear Seat Outside Passenger Positions.............1-26
Rear Seat Passengers, Safety Belts..........1-25, 1-26
Rearview Mirror, Automatic Dimming..................2-39
Rearview Mirrors.............................................2-39
Reclining Seatbacks.......................................... 1-6
Recreational Vehicle Towing.............................4-42
Regular Cab and Extended Cab Models.............1-60
Remote Keyless Entry System............................ 2-4
Remote Keyless Entry System, Operation............ 2-5
Removing the Flat Tire and Installing the
Spare Tire..................................................5-71
Removing the Spare Tire and Tools...................5-68
Removing Wheel Covers..................................5-70
Replacement Bulbs.........................................5-55
Replacing Brake System Parts..........................5-42
Replacing Restraint System Parts
After a Crash..............................................1-64
Reporting Safety Defects
Canadian Government................................... 7-9
General Motors............................................. 7-9
United States Government
.............................. 7-8
Restraint System Check
...................................6-26
Checking Your Restraint Systems
...................1-64
Replacing Restraint System Parts
After a Crash
..........................................1-64Restraint Systems
Checking....................................................1-64
Replacing Parts...........................................1-64
Retained Accessory Power (RAP)......................2-22
Right Front Passenger Position, Safety Belts......1-23
Roadside
Assistance Program....................................... 7-5
Rocking Your Vehicle To Get It Out...................4-40
Running Your Engine While You Are Parked.......2-38
S
Safety Belt
Reminder Light............................................3-23
Safety Belts
Care of ......................................................5-82
Center Passenger Position............................1-23
Driver Position............................................1-16
How to Wear Safety Belts Properly................1-15
Questions and Answers About
Safety Belts.............................................1-15
Rear Seat Passengers.........................1-25, 1-26
Right Front Passenger Position......................1-23
Safety Belt Extender....................................1-29
Safety Belt Use During Pregnancy.................1-22
Safety Belts Are for Everyone.......................1-10
Safety Chains.................................................4-56
Safety Warnings and Symbols.............................. iii
Scanning the Terrain.......................................4-16
12
2003 - Sonoma OM

Vinyl.............................................................5-80
Visors...........................................................2-16
Voltmeter Gage..............................................3-26
W
Warning Lights, Gages and Indicators................3-20
Warnings
Hazard Warning Flashers............................... 3-3
Other Warning Devices.................................. 3-4
Safety and Symbols......................................... iii
Vehicle Damage.............................................. iv
Washing Your Vehicle......................................5-82
Weatherstrip Lubrication...................................6-27
Weight of the Trailer........................................4-53
Weight of the Trailer Tongue.............................4-55
What Kind of Engine Oil to Use........................5-14
What to Add ..................................................5-40
What to Do with Used Oil ................................5-17
What to Use ..........................5-26, 5-38, 5-47, 5-49
Wheels
Alignment and Tire Balance..........................5-64
Replacement...............................................5-65
When to Add Engine Oil..................................5-13
When to Change Engine Oil.............................5-16
When to Check......................................5-23, 5-59
When to Check and Change............................5-20
When to Check and Change Lubricant.......5-47, 5-49When to Check and What to Use.....................5-24
When to Check Power Steering Fluid................5-37
When to Inspect the Engine Air Cleaner/Filter.....5-19
When You Are Ready to Leave
After Parking on a Hill..................................4-60
Where to Put the Restraint.......................1-39, 1-40
Why Safety Belts Work....................................1-12
Window Lockout.............................................2-15
Windows.......................................................2-14
Manual......................................................2-15
Power ........................................................2-15
Sliding Rear................................................2-16
Swing-Out Windows.....................................2-16
Windshield and Wiper Blades...........................5-84
Windshield Washer........................................... 3-7
Fluid..........................................................5-38
Windshield Washer Fluid Level Check................6-26
Windshield Wiper
Blade Replacement......................................5-56
Fuses........................................................5-88
Windshield Wipers............................................ 3-7
Winter Driving................................................4-36
Wiper Blade Check.........................................6-27
Wood Panels.................................................5-81
Y
Your Vehicle and the Environment....................... 6-2
16
2003 - Sonoma OM