2002 GMC SONOMA light

2-79
Emissions Inspection and Maintenance Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know in order to help
your vehicle pass an inspection:
Your vehicle will not pass this inspection if the
SERVICE ENGINE SOON or CHECK ENGINE light is
on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on
-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen if
you have recently replaced your battery or if your
battery has run down. The diagnostic system is designed
to evaluate critical emission control systems during
normal driving. This may take several days of routine
driving. If you have done this and your vehicle still does
not pass the inspection for lack of OBD system
readiness, see your dealer or qualified service center to
prepare the vehicle for inspection.
Oil Pressure Gage
United States Canada
The oil pressure gage shows the engine oil pressure
in psi (pounds per square inch) when the engine is
running. Canadian vehicles indicate oil pressure in
kPa (kilopascals).

2-80
CAUTION:
Don't keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches fire. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
NOTICE:
Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
A reading in the low pressure zone may be caused by a
dangerously low oil level or other problems causing low
oil pressure.
Security Light
This light will come on
briefly when you turn the
key toward START. The
light will stay on until the
engine starts.
If the light flashes, the Passlock

system has entered a
tamper mode. If the vehicle fails to start, see ªPasslockº
in the Index.
If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
system. Your vehicle will not be protected by Passlock,
and you should see your dealer.
Also see ªContent Theft
-Deterrentº in the Index for
additional information regarding the SECURITY light.

2-81 Service Four-Wheel-Drive Warning Light
This light should come on
briefly when you turn on the
ignition, as a check to show
you it is working.
The SERVICE 4WD light comes on to indicate that
there may be a problem with the four
-wheel drive
system and service is required. Malfunctions can be
indicated by the system before any problem is apparent,
which may prevent serious damage to the vehicle. This
system is also designed to assist your service technician
in correctly diagnosing a malfunction.
Check Gages Light
If this light comes on and
stays on while you are
driving, check your coolant
temperature and engine oil
pressure gages to see if they
are in the warning zones.

2-83 Low Fuel Light
This light comes on briefly
when you start your engine.
This light comes on when the fuel tank is low on fuel.
To turn it off, add fuel to the fuel tank. See ªFuelº in
the Index.
Driver Information Center (DIC) (If Equipped)
This system displays the outside air temperature,
compass direction and trip information in the
overhead console.
US/MET (United States/Metric): The US/MET
(United States/metric) button allows you to switch the
display between the English and metric system.
MODE: The MODE button can be used to toggle
between three modes of operation: OFF, COMP/TEMP
and TRIP.COMP/TEMP (Compass/Temperature): The
display provides the outside temperature and one of
eight compass readings to indicate the direction the
vehicle is facing.
Before you turn on the ignition and move the vehicle,
the temperature indicated will be the last outside
temperature recorded with the ignition on. If the outside
temperature is 37
F (3
C) or lower, the display will
toggle between the word ICE and the current
temperature every eight seconds. This is a warning to
the driver that road conditions may be icy, and that
appropriate precautions should be taken.
The compass is self
-calibrating, so it does not need to be
manually set. However, if ªCº (Calibration) is
displayed, the compass will need to be calibrated. You
may also place the compass in a noncalibrated mode by
pressing and holding the MODE and US/MET buttons
simultaneously while in the COMP/TEMP mode. After
about 10 seconds, the compass will display C and you
can release the buttons. Drive the vehicle in a complete
360
circle three times at a speed of less than 5 mph
(8 km/h), and the compass will function normally. Once
the calibration is complete, the display will return to a
compass reading.

3-5 Air Conditioning (If Equipped)
On hot days, open the windows long enough to let hot
inside air escape. This reduces the time it takes for your
vehicle to cool down. Then keep your windows closed
for the air conditioner to work its best.
For quick cool
-down on very hot days, use MAX A/C
with the temperature knob turned counterclockwise.
This setting should be used to keep odors and/or dust
from entering the vehicle. For normal cooling on hot
days, use A/C with the temperature knob turned
counterclockwise.
On cool but sunny days, use bi
-level to deliver warm
air to the floor and cooler air to the instrument
panel outlets.
If you have the VORTEC 4300 V6 engine, when the air
conditioner is on, you may sometimes notice slight
changes in your vehicle's engine speed and power. This
is normal because the system is designed to cycle the
compressor on and off to keep the desired temperature.
Heating
The heater works best if you keep your windows closed
while using it. On cold days, use the floor outlets with
the temperature knob turned clockwise. Blend is useful
in cool weather when you have fog or ice on the
windshield or side windows.
If you use the optional engine coolant heater before
starting your engine, your heating system will produce
warmer air faster to heat the passenger compartment in
cold weather. See ªEngine Coolant Heaterº in the Index.

3-17
RECALL: Pressing this button will display the station
being played or it will display the clock. Clock display
is available with the ignition turned off.
SCV (Speed
-Compensated Volume): With SCV, your
audio system adjusts automatically to make up for road
and wind noise as you drive. Set the volume at the
desired level. Turn the control ring behind the upper
knob clockwise to adjust the SCV. Each notch on the
control ring allows for more volume compensation at
faster vehicle speeds. Then, as you drive, SCV
automatically increases the volume, as necessary, to
overcome noise at any speed. The volume level should
always sound the same to you as you drive. If you don't
want to use SCV, turn the control all the way down.
Finding a Station
AM FM: Press this button to switch between AM, FM1
and FM2. The display will show your selection.
TUNE: Press this knob lightly so it extends. Turn it to
choose radio stations. Push the knob back into its stored
position when you're not using it.
SEEK : Press the right or left arrow to seek to
the next or previous station and stay there. The radio
will seek to stations with a strong signal only. The sound
will mute while seeking.
To scan station, press and hold SEEK for two seconds
until SCAN appears on the display. The radio will go to
a station, play for a few seconds and flash the station
frequency, then go on to the next station. Press one of
the SEEK arrows again to stop scanning. The radio will
scan to stations with a strong signal only. The sound will
mute while scanning.
P.SCAN (Preset Scan): Press this button and P. SCAN
will appear on the display. The radio will go to the first
preset station stored on your pushbuttons, play for a few
seconds and flash the station frequency, then go on to
the next preset station. This feature will only scan the
six presets that are in the selected band. Press this button
again or a pushbutton to stop scanning presets. The
channel number (P1
-P6) will appear momentarily just
before the frequency is displayed. The radio will scan
preset stations with a strong signal only. The sound will
mute while scanning.

3-18
Setting Preset Stations
The six numbered pushbuttons let you return to
your favorite stations. You can set up to 18 stations
(six AM, six FM1 and six FM2) by performing the
following steps:
1. Turn the radio on.
2. Press AM FM to select AM, FM1 or FM2.
3. Tune in the desired station.
4. Press AUTO TONE to select the setting you prefer.
5. Press and hold one of the six pushbuttons. The sound
will mute. When it returns, release the button.
Whenever you press that numbered pushbutton, the
station you set will return and the tone you selected
will be automatically selected for that pushbutton.
6. Repeat the steps for each pushbutton.Setting the Tone (Bass/Treble)
BASS: Press this knob lightly so it extends. Turn the
knob clockwise to increase bass and counterclockwise to
decrease bass.
TREB: Press this knob lightly so it extends. Turn the
knob clockwise to increase treble and counterclockwise
to decrease treble. If a station is weak or noisy, you may
want to decrease the treble.
Push these knobs back into their stored positions when
you're not using them.
AUTO TONE: This feature allows you to choose
bass and treble equalization settings designed for
country/western, jazz, talk, pop, rock and
classical stations.
Each time you press the AUTO TONE button, this
feature will switch to one of these program types.
To return the bass and treble to the manual mode, either
press and release the AUTO TONE button until the
display goes blank or press and release the BASS or
TREB knobs and turn them until the display goes blank.

3-19
Adjusting the Speakers (Balance/Fade)
BAL (Balance): Press this knob lightly so it extends.
Turn the knob clockwise to adjust sound to the right
speakers and counterclockwise to adjust sound to the left
speakers. The middle position balances the sound
between the speakers.
FADE: Press this knob lightly so it extends. Turn the
knob clockwise to adjust the sound to the front speakers
and counterclockwise for the rear speakers. The middle
position balances the sound between the speakers.
Push these knobs back into their stored positions when
you're not using them.
Playing a Cassette Tape
Your tape player is built to work best with tapes that are
up to 30 to 45 minutes long on each side. Tapes longer
than that are so thin they may not work well in
this player.
To load a cassette tape with the ignition off, press
EJECT or RECALL. Then, insert the cassette tape.
If the ignition is on but the radio is off, the tape will
begin playing.Once the tape is playing, use the VOL, AUTO TONE,
BAL, FADE, BASS and TREB controls just as you do
for the radio. The tape symbol and a direction arrow will
be on the display whenever a tape is being played.
Anytime a tape is inserted, the top side is selected for
play first.
The player automatically senses if the cassette tape is
metal or CrO
2 and adjusts for best playback sound.
If an error appears on the display, see ªCassette Tape
Messagesº later in this section.
1 PREV (Previous): Press this pushbutton or the left
SEEK arrow to search for the previous selection. A
minimum three
-second blank gap is required for the
player to stop at the beginning of the selection. The tape
direction arrow will blink while in previous mode.
2 PROG (Program): Press this pushbutton to switch
from one side of the tape to the other.
3 NEXT: Press this pushbutton or the right SEEK arrow
to search for the next selection. A minimum
three
-second blank gap is required for the player to stop
at the beginning of the selection. The tape direction
arrow will blink while in next mode. The sound will
mute while searching for the next selection.