Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-3
Rear Seats
............................................... 1-9
Safety Belts
.............................................1-10
Child Restraints
.......................................1-30
Air Bag System
.......................................1-54
Restraint System Check
............................1-64
Features and Controls..................................... 2-1
Keys
........................................................ 2-3
Doors and Locks
....................................... 2-8
Windows
.................................................2-14
Theft-Deterrent Systems
............................2-17
Starting and Operating Your Vehicle
...........2-20
Mirrors
....................................................2-39
Storage Areas
.........................................2-41
Sunroof
..................................................2-52
Vehicle Personalization
.............................2-54
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-2
Climate Controls
......................................3-17
Warning Lights, Gages and Indicators
.........3-20
Audio System(s)
.......................................3-36
Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-42Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-4
Checking Things Under the Hood
................. 5-8
Rear Axle
...............................................5-47
Four-Wheel Drive
.....................................5-48
Front Axle
...............................................5-49
Bulb Replacement
....................................5-50
Windshield Wiper Blade Replacement
.........5-56
Tires
......................................................5-58
Appearance Care
.....................................5-79
Vehicle Identification
.................................5-87
Electrical System
......................................5-88
Capacities and Specifications
.....................5-94
Normal Maintenance Replacement Parts
......5-96
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 Sonoma Owner ManualM
2003 - Sonoma Owner Manual
Vehicle Damage Warnings
Also, in this book you willfind these notices:
Notice:These mean there is something that could
damage your vehicle.
A notice will tell you about something that can damage
your vehicle. Many times, this damage would not be
covered by your warranty, and it could be costly. But the
notice will tell you what to do to help avoid the
damage.
When you read other manuals, you might see CAUTION
and NOTICE warnings in different colors or in different
words.
You’ll also see warning labels on your vehicle. They use
the same words, CAUTION or NOTICE.
Vehicle Symbols
Your vehicle has components and labels that use
symbols instead of text. Symbols, used on your vehicle,
are shown along with the text describing the operation
or information relating to a specific component, control,
message, gage or indicator.
If you need helpfiguring out a specificnameofa
component, gage or indicator, reference the following
topics:
•Seats and Restraint Systems in Section 1
•Features and Controls in Section 2
•Instrument Panel Overview in Section 3
•Climate Controls in Section 3
•Warning Lights, Gages and Indicators in Section 3
•Audio System(s) in Section 3
•Engine Compartment Overview in Section 5
iv
2003 - Sonoma OM
Changes or modifications to this system by other than
an authorized service facility could void authorization
to use this equipment.
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 2-5.
•If you are still having trouble, see your dealer or
a qualified technician for service.
Remote Keyless Entry System
Operation
If your vehicle has this feature, you can lock and unlock
your doors from about 3 feet (1 m) up to 30 feet (9 m)
away using the remote keyless entry transmitter supplied
with your vehicle.
UNLOCK:When you
press UNLOCK, the
driver’s door will unlock
automatically, the parking
lamps willflash and the
interior lights will go on.
If you press UNLOCK again within three seconds, the
remaining doors will unlock, the parking lamps willflash
and the interior lights will go on.
LOCK:Press LOCK to lock all the doors. Press LOCK
again within three seconds and the horn will chirp.
2-5
2003 - Sonoma OM
Electronic Transfer Case
If your four-wheel-drive
vehicle has the electronic
transfer case, the transfer
case buttons are to the
right of the steering wheel
on the instrument panel.
Use these buttons to shift into and out of
four-wheel-drive. You can choose among three driving
settings:
2HI:This setting is for driving in most street and
highway situations. Your front axle is not engaged in
two-wheel drive. When this light is turned on, it is about
one-half as bright as the others.4HI:This setting engages your front axle to help drive
your vehicle. Use 4HI when you need extra traction,
such as on snowy or icy roads, or in most off-road
situations.
4LO:You may never need 4LO. This setting also
engages your front axle to give you extra traction. It
sends the maximum power to all four wheels. You might
choose 4LO if you were driving off-road in sand, mud
or deep snow and climbing or descending steep hills.
Indicator lights in the buttons show you which setting
you are in. The indicator lights will come on briefly when
you turn on the ignition and one will stay on. If the
lights do not come on, you should take your vehicle in
for service. An indicator light willflash while shifting.
It will remain illuminated when the shift is completed.
Shifting from 2HI to 4HI
Press and release the 4HI button. This can be done at
any speed, and the front axle will lock automatically.
Shifting from 4HI to 2HI
Press and release the 2HI button. This can be done at
any speed, and the front axle will unlock automatically.
2-30
2003 - Sonoma OM
Mirrors
Manual Rearview Mirror
Pull the tab under the mirror toward you to reduce the
glare from headlamps behind you after dark. Push
the tab away from you for normal daytime operation.
Automatic Dimming Rearview Mirror
If your vehicle has this feature, the mirror automatically
changes to reduce glare from headlamps behind
you. A photocell on the back of the mirror senses when
it is becoming dark outside. Another photocell built
into the mirror surface senses when headlamps
are behind you.
At night, when the glare is too high, the mirror will
gradually darken to reduce glare. This change may take a
few seconds. The mirror will return to its clear daytime
state when the vehicle is put into REVERSE (R) or when
the glare is reduced.
AUTO:This button is located at the base of the mirror.
Use it to turn on the automatic feature. The button
has an indicator light to show it is on.
OFF:Press this button to turn the automatic feature off.
Time Delay
The automatic mirror has a time delay feature which
prevents unnecessary switching from the night back to
the day position. This delay prevents rapid changing
of the mirror as you drive under lights and through traffic.
Cleaning the Photocells
Use a cotton swab and glass cleaner to clean the
photocells and mirror face when necessary.
Cleaning the Mirror
When cleaning the mirror, use a paper towel or similar
material dampened with glass cleaner. Do not spray
glass cleaner directly on the mirror as that may cause
the liquid cleaner to enter the mirror housing.
Outside Manual Mirror
Adjust your outside mirrors so you can see a little of the
side of your vehicle and the area beside and behind
your vehicle from a comfortable driving position.
You can also fold the mirrors in before entering a car
wash. Pull the mirrors in toward the vehicle. Push
the mirrors back out whenfinished.
2-39
2003 - Sonoma OM
Instrument Panel Overview...............................3-2
Hazard Warning Flashers................................3-3
Other Warning Devices...................................3-4
Horn .............................................................3-4
Tilt Wheel.....................................................3-4
Turn Signal/Multifunction Lever.........................3-5
Exterior Lamps.............................................3-10
Interior Lamps..............................................3-14
Accessory Power Outlets...............................3-15
Ashtrays and Cigarette Lighter........................3-16
Climate Controls............................................3-17
Climate Control System.................................3-17
Outlet Adjustment.........................................3-19
Warning Lights, Gages and Indicators.............3-20
Instrument Panel Cluster................................3-21
Speedometer and Odometer...........................3-23
Trip Odometer..............................................3-23
Tachometer.................................................3-23
Safety Belt Reminder Light.............................3-23
Air Bag Readiness Light................................3-24
Air Bag Off Light..........................................3-24
Charging System Light..................................3-26
Voltmeter Gage............................................3-26
Up-Shift Light...............................................3-27
Brake System Warning Light..........................3-27Anti-Lock Brake System Warning Light.............3-28
Engine Coolant Temperature Gage..................3-29
Malfunction Indicator Lamp.............................3-29
Oil Pressure Gage........................................3-32
Security Light...............................................3-33
Service Four-Wheel Drive Warning Light..........3-34
Check Gages Warning Light...........................3-34
Fuel Gage...................................................3-35
Low Fuel Warning Light.................................3-35
Audio System(s).............................................3-36
Setting the Time for Radios without Radio
Data Systems (RDS)..................................3-36
Setting the Time for Radios with Radio
Data Systems (RDS)..................................3-37
AM-FM Radio...............................................3-37
Radio with CD..............................................3-40
Radio with Cassette and CD..........................3-47
Radio with Six-Disc CD.................................3-56
Theft-Deterrent Feature (Non-RDS Radios).......3-67
Theft-Deterrent Feature (RDS Radios).............3-67
Understanding Radio Reception......................3-67
Care of Your Cassette Tape Player.................3-68
Care of Your CDs
.........................................3-69
Care of Your CD Player
................................3-69
Fixed Mast Antenna
......................................3-69
Section 3 Instrument Panel
3-1
2003 - Sonoma OM
;(Parking Lamps):Turning the exterior lamps
control to this position turns on the parking lamps
together with the following:
Sidemarker Lamps
Taillamps
License Plate Lamps
Instrument Panel Lights
O(Headlamps):Turning the exterior lamps control to
this position turns on the headlamps, together with
the previously listed lamps and lights.
Automatic Headlamp System
When it is dark enough outside, your automatic
headlamp system will turn on your headlamps at the
normal brightness along with other lamps such as
the taillamps, sidemarker, parking lamps and the
instrument panel lights. The radio lights will also be dim.
Your vehicle is equipped with a light sensor on the
top of the instrument panel under the radio speaker grill.
Be sure it is not covered or the system will be on
whenever the ignition is on.
The system may also turn on your headlamps when
driving through a parking garage, heavy overcast
weather or a tunnel. This is normal.There is a delay in the transition between the daytime
and nighttime operation of the Daytime Running
Lamps (DRL) and the automatic headlamp systems so
that driving under bridges or bright overhead street
lights does not affect the system. The DRL and
automatic headlamp system will only be affected when
the light sensor sees a change in lighting lasting
longer than the delay.
To idle your vehicle with the automatic headlamp
system off, set the parking brake while the ignition is off.
Then start your vehicle. The automatic headlamp
system will stay off until you release the parking brake.
As with any vehicle, you should turn on the regular
headlamps when you need them.
You may be able to turn off your automatic headlamp
system. See“Daytime Running Lamps (DRL)”later
in this section for more information.
If you start your vehicle in a dark garage, the automatic
headlamp system will come on immediately. Once
you leave the garage, it will take approximately
one minute for the automatic headlamp system to
change to DRL if it is light outside. During that delay,
your instrument panel cluster may not be as bright
as usual. Make sure your instrument panel brightness
control is in the full bright position. See“Instrument
Panel Brightness Control”underInterior Lamps
on page 3-14.
3-11
2003 - Sonoma OM
Interior Lamps
Instrument Panel Brightness
This feature controls the brightness of the instrument
panel lights.
It is located on the driver’s side of your instrument panel
next to the exterior lamps control.
Turn the thumbwheel up to make your instrument panel
lights brighter or down to dim them. Turn the
thumbwheel all the way up to turn on the interior lamps.
Entry Lighting
Your vehicle is equipped with an entry lighting feature.
When any door is opened, the dome lamps will
come on if the DOME OVERRIDE button is in the out
position. If your vehicle is equipped with remote keyless
entry and all the doors are closed, or the front door
handles are lifted and released, the lamps will stay on
for a short period of time and will turn off automatically.
If you use your remote keyless entry transmitter to
unlock the vehicle, the interior lights will come on for a
short time whether or not the DOME OVERRIDE
button is in the out position.
Exit Lighting
With exit lighting, the interior lamps will come on when
you remove the key from the ignition to help you
see while exiting the vehicle. These lights will stay on
for a short period of time and then will go out, if the
DOME OVERRIDE button is in the out position.
Front Map Lamps
If your vehicle is a Crew Cab®and has front map
lamps, they are located in the overhead console. For all
other vehicles that have this feature, they are located
on the inside rearview mirror. The front map lights
that are located on the inside rearview mirror will
automatically come on for approximately 40 seconds
when the doors are unlocked with the remote keyless
entry transmitter (if equipped) or until the ignition key is
turned to RUN or ACCESSORY. The lamps will also
stay on for approximately 40 seconds after you exit the
vehicle, unless you lock the doors with the remote
keyless entry transmitter.
You can also turn the lamps on and off by pressing the
switch near each lamp.
3-14
2003 - Sonoma OM