2003 GMC SONOMA ignition

The SERVICE ENGINE SOON or CHECK ENGINE light
comes on to indicate that there is a problem and
service is required. Malfunctions often will be indicated
by the system before any problem is apparent. This
may prevent more serious damage to your vehicle. This
system is also designed to assist your service
technician in correctly diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after a while, your emission controls
may not work as well, your fuel economy may not
be as good and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake or fuel system of your
vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is not
running. If the light doesn’t come on, have it repaired.This light will also come on during a malfunction in one of
two ways:
Light Flashing—Amisre condition has been
detected. A misre increases vehicle emissions and
may damage the emission control system on your
vehicle. Diagnosis and service may be required.
Light On Steady—An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
If the Light Is Flashing
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed.
Avoiding hard accelerations.
Avoiding steep uphill grades.
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stopsashing and remains on steady, see
“If the Light Is On Steady”following.
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Service Four-Wheel Drive Warning
Light
If you have this light,
it should come on briey
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 Warning Light
The CHECK GAGES
light will come on briey
when you are starting
the engine.
If this light comes 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.
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Fuel Gage
When the ignition is on, the fuel gage tells you about
how much fuel you have remaining.
Here are four things that some owners ask about.
None of these show a problem with your fuel gage:
At the gas station, the gas pump shuts off before the
gage reads full.
It takes a little more or less fuel toll up than the
gage indicated. For example, the gage may have
indicated the tank was half full, but it actually took a
little more or less than half the tank’s capacity to
ll the tank.
The gage moves a little when you turn a corner or
speed up.
The gage doesn’t go back to empty when you turn
off the ignition.
Low Fuel Warning Light
This light comes on
briey when you start
your engine.
This light comes on when the fuel tank is low on fuel.
To turn if off, add fuel to the fuel tank. SeeFilling Your
Tank on page 5-6. United States
Canada
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Audio System(s)
Notice:Before you add any sound equipment to
your vehicle—like a tape player, CB radio, mobile
telephone or two-way radio—be sure you can
add what you want. If you can, it’s very important to
do it properly. Added sound equipment may
interfere with the operation of your vehicle’s engine,
Delphi Electronics radio or other systems, and
even damage them. Your vehicle’s systems may
interfere with the operation of sound equipment that
has been added improperly.
So, before adding sound equipment, check with
your dealer and be sure to check federal rules
covering mobile radio and telephone units.
Your audio system has been designed to operate easily
and to give years of listening pleasure. You will get the
most enjoyment out of it if you acquaint yourself with it
rst. Find out what your audio system can do and how to
operate all of its controls to be sure you’re getting the
most out of the advanced engineering that went into it.Your vehicle has a feature called Retained Accessory
Power (RAP). With RAP, you can play your audio
system even after the ignition is turned off. See
“Retained Accessory Power (RAP)”underIgnition
Positions on page 2-20.
Setting the Time for Radios without
Radio Data Systems (RDS)
Press and hold HR until the correct hour appears on the
display. Press and hold MN until the correct minute
appears on the display. To display the time with
the ignition off, press RECALL or HR/MN and the time
will be displayed for a few seconds. There is an
initial two-second delay before the clock goes into the
time-set mode.
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Setting the Time for Radios with
Radio Data Systems (RDS)
Your radio may have a button marked with an H or HR to
represent hours and an M or MIN to represent minutes.
Press and hold the hour button until the correct hour
appears on the display. AM or PM will also appear on
the display. Press and hold the minute button until
the correct minute appears on the display. The time may
be set with the ignition on or off.
To synchronize the time with an FM station broadcasting
Radio Data System (RDS) information, press and
hold the hour and minute buttons at the same time for
two seconds until UPDATED and the clock symbol
appear on the display. If the time is not available from
the station, NO UPDAT will appear on the display
instead.
RDS time is broadcast once a minute. Once you have
tuned to an RDS broadcast station, it may take a
few minutes for your time to update.
AM-FM Radio
Playing the Radio
PWR (Power):Press this knob to turn the system
on and off.
VOL (Volume):Turn the knob to increase or to
decrease volume.
RCL (Recall):Press this knob to switch the display
between time and radio station frequency. Time
display is available with the ignition turned off.
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Finding a Station
AM FM:Press this button to switch the display between
time and radio station frequency. Time display is
available with the ignition turned off.
TUNE:Turn this knob to tune in radio stations.
oSEEKp:Press the right or the left arrow to seek
to the next or to the previous station and stay there.
To scan stations, press and hold one of the SEEK
arrows for two seconds until you hear a beep. The radio
will go to a station, play for a few seconds andash
the station frequency, then go on to the next station.
Press one of the SEEK arrows again to stop scanning.
To scan preset stations, press and hold one of the
SEEK arrows for more than four seconds until you hear
two beeps. The radio will go to therst preset station
stored on the pushbuttons, play for a few seconds
andash the station frequency, then go on to the next
preset station. Press one of the SEEK arrows again
to stop scanning presets.
This radio will seek and scan only to stations that are in
the selected band and only to those with a strong signal.
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 and hold one of the six numbered
pushbuttons until you hear a beep. Whenever you
press that numbered pushbutton, the station
you set will return.
5. Repeat the steps for each pushbutton.
Setting the Tone (Bass/Treble)
AUDIO:To adjust bass and treble, press and release
AUDIO repeatedly until BAS or TRE appears on
the display. Then press and hold the up or the down
arrow to increase or to decrease. If a station is weak or
noisy, you may want to decrease the treble.
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Radio with CD
Playing the Radio
PWR (Power):Press this knob to turn the system
on and off.
VOL (Volume):Turn this knob to increase or to
decrease volume.
AUTO VOL (Automatic Volume):With automatic
volume, your audio system will adjust automatically to
make up for road and wind noise as you drive.Set the volume at the desired level. Press this button to
select LOW, MEDIUM or HIGH. AVOL will appear on
the display. Each higher setting will allow for more
volume compensation as vehicle speed increases.
The volume level should always sound the same to you
as you drive. To turn automatic volume off, press this
button until AVOL OFF appears on the display.
DISP (Display):Press this button to switch the display
between the radio station frequency and the time.
Time display is available with the ignition turned off.
To change the default on the display, push the knob until
you see the display you want, then hold the knob for
two seconds. The radio will produce one beep and
selected display will now be the default.
Finding a Station
AM FM:Press this button to switch between AM, FM1
and FM2. The display will show your selection.
TUNE:Turn this knob to choose radio stations.
qSEEKr:Press the right or the left arrow to seek
to the next or to the previous station and stay there.
The radio will seek only to stations that are in the
selected band and only to those with a strong signal.
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Finding a PTY Station
To select andnd a desired PTY perform the following:
1. Press the P-TYPE LIST knob. TYPE and
a PTY will appear on the display.
2. Select a category by turning the P-TYPE
LIST knob.
3. Once the desired category is displayed, press the
SEEK TYPE button to take you to the category’s
rst station.
4. If you want to go to another station within that
category and the category is displayed, press
the SEEK TYPE button once. If the category
is not displayed, press the SEEK TYPE button
twice to display the category and then to go
to another station.
If the radio cannotnd the desired program type, NONE
will appear on the display and the radio will return to
the last station you were listening to.AM FM (Alternate Frequency):Alternate frequency
allows the radio to switch to a stronger station with the
same program type. Press and hold AM FM for two
seconds to turn alternate frequency on. AF ON
will appear on the display. The radio may switch to
stronger stations. Press and hold AM FM again for two
seconds to turn alternate frequency off. AF OFF will
appear on the display. The radio will not switch to other
stations. When you turn the ignition off and then on
again, the alternate frequency feature will automatically
be turned on.
RDS Messages
ALERT!:Alert warns of local or national emergencies.
When an alert announcement comes on the current
radio station, ALERT! will appear on the display. You will
hear the announcement, even if the volume is muted
or a compact disc is playing. If the compact disc player
is playing, play will stop during the announcement.
You will not be able to turn off alert announcements.
ALERT! will not be affected by tests of the emergency
broadcast system. This feature is not supported by
all RDS stations.
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