2003 GMC SONOMA service indicator

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

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

Shifting from 2HI or 4HI to 4LO
To shift from 2HI or 4HI to 4LO, the vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with the
transmission in NEUTRAL (N) in vehicles equipped
with an automatic transmission or the clutch pedal
engaged in vehicles equipped with a manual
transmission. The preferred method for shifting into 4LO
is to have your vehicle moving 1 to 2 mph
(1.6 to 3.2 km/h). Press and release the 4LO button.
You must wait for the 4LO indicator light to stopflashing
and remain illuminated before shifting your transmission
into gear or releasing the clutch pedal.
If the 4LO button is pressed when your vehicle is in
gear and/or moving, the 4LO indicator light willflash for
30 seconds and not complete the shift unless your
vehicle is moving slower than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N) or the clutch pedal
engaged.
On automatic transmission equipped vehicles, if your
transfer case does not shift into 4LO, your transmission
indicator switch may require adjustment. With your
transmission in NEUTRAL (N), press and release the
4LO button. While the 4LO indicator light isflashing, shift
your transmission into PARK (P). Wait until the 4LO
indicator light remains illuminated before shifting
your transmission into gear. This will get you into 4LO,
but you should take your vehicle in for service to
restore normal operation.
Shifting from 4LO to 4HI or 2HI
To shift from 4LO to 4HI or 2HI, your vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with
the transmission in NEUTRAL (N) or the clutch pedal
engaged. The preferred method for shifting out of 4LO
is to have your vehicle moving 1 to 2 mph
(1.6 to 3.2 km/h). Press and release the 4HI button.
You must wait for the 4HI indicator light to stopflashing
and remain illuminated before shifting your transmission
into gear or releasing the clutch pedal.
If the 4HI button is pressed when your vehicle is in gear
and/or moving, the 4HI indicator light willflash for
30 seconds but not complete the shift unless the vehicle
is moving slower than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N) or the clutch pedal
engaged.
On automatic transmission equipped vehicles, if your
transfer case does not shift into 4HI, your transmission
indicator switch may require adjustment. With your
transmission in NEUTRAL (N), press and release the
4HI button. While the 4HI indicator light isflashing, shift
your transmission into PARK (P). Wait until the 4HI
indicator light remains illuminated before shifting your
transmission into gear. This will get you into 4HI, but you
should take your vehicle in for service to restore
normal operation.
2-31
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

You can only drive for a short time with the reading in
either warning zone. If you must drive, turn off all
unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
Up-Shift Light
You have the shift light if
you have a manual
transmission.
Shifting when the indicator light is on will help you get
the best fuel economy. See“Up-Shift Light”under
Manual Transmission Operation on page 2-28.
Brake System Warning Light
When the ignition is on, the brake system warning light
will come on when you set your parking brake. The
light will stay on if your parking brake doesn’t release
fully. If it stays on after your parking brake is fully
released, it means you have a brake problem.
Your vehicle’s hydraulic brake system is divided into two
parts. If one part isn’t working, the other part can still
work and stop you. For good braking, though, you need
both parts working well.
If the warning light comes on, there could be a brake
problem. Have your brake system inspected right away.
This light should come on briey when you turn the
ignition key to RUN. If it doesn’t come on then, have it
xed so it will be ready to warn you if there’s a problem.
United StatesCanada
3-27
2003 - Sonoma OM

Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
If the gage pointer moves into the red area, your engine
is too hot!
It means that your engine coolant has overheated.
If you have been operating your vehicle under normal
driving conditions, you should pull off the road, stop your
vehicle and turn off the engine as soon as possible.
SeeEngine Overheating on page 5-28for more
information.
Malfunction Indicator Lamp
Service Engine Soon Light in the
United States or Check Engine Light
in Canada
Your vehicle is equipped with a computer which
monitors operation of the fuel, ignition and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. United States
Canada
United StatesCanada
3-29
2003 - Sonoma OM

After you clean the player, press and hold the EJT button
forve seconds to reset the CLEAN indicator. The radio
will display CLEANED to show the indicator was reset.
Cassettes are subject to wear and the sound quality may
degrade over time. Always make sure the cassette
tape is in good condition before you have your
tape player serviced.
Care of Your CDs
Handle discs carefully. Store them in their original cases
or other protective cases and away from direct sunlight
and dust. If the surface of a disc is soiled, dampen
a clean, soft cloth in a mild, neutral detergent solution
and clean it, wiping from the center to the edge.
Be sure never to touch the side without writing when
handling discs. Pick up discs by grasping the outer
edges or the edge of the hole and the outer edge.
Care of Your CD Player
The use of CD lens cleaner discs is not advised,
due to the risk of contaminating the lens of the CD optics
with lubricants internal to the CD mechanism.
Fixed Mast Antenna
Thexed mast antenna can withstand most car washes
without being damaged. If the mast should ever
become slightly bent, you can straighten it out by hand.
If the mast is badly bent, as it might be by vandals,
you should replace it.
Check occasionally to be sure the mast is still tightened
to the fender. If tightening is required, tighten by
hand, then with a wrench one quarter turn.
3-69
2003 - Sonoma OM

Notice:Yourvehicle was not designed for fuel that
contains methanol. Don’t use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber parts.
That damage wouldn’t be covered under your
warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may
be affected. The malfunction indicator lamp may turn on.
If this occurs, return to your authorized GM dealer for
service.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may be hard
tofind. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel wouldn’tbe
covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you’ll be driving.
Filling Your Tank
{CAUTION:
Fuel vapor is highly ammable. It burns
violently, and that can cause very bad injuries.
Don’t smoke if you’re near fuel or refueling
your vehicle. Keep sparks, ames and smoking
materials away from fuel.
The fuel cap is located behind a hinged door on the
driver’s side of your vehicle.
5-6
2003 - Sonoma OM