light GMC SONOMA 2003 Service Manual

If the light continues toash, when it is safe to do so,stop
the vehicle.Find a safe place to park your vehicle. Turn
the key off, wait at least 10 seconds and restart the
engine. If the light remains on steady, see“If the Light Is
On Steady”following. If the light is stillashing, follow the
previous steps, and see your dealer for service as soon
as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. SeeFilling Your Tank on page 5-6. The
diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-4. Poor fuel quality will
cause your engine not to run as efficiently as designed.
You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, misring, hesitation
on acceleration or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the
light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer can check the vehicle. Your dealer has
the proper test equipment and diagnostic tools tox any
mechanical or electrical problems that may have
developed.
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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 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, your
GM dealer can prepare the vehicle for inspection.
Oil Pressure Gage
The oil pressure gage shows the engine oil pressure in
psi (pounds per square inch) when the engine is
running. Canadian vehicles indicate pressure in kPa
(kilopascals).United States
Canada
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{CAUTION:
Don’t keep driving if the oil pressure is low.
If you do, your engine can become so hot that
it catchesre. 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
briey when you turn the
key toward START.
The light will stay on until
the engine starts.
If the lightashes, the Passlock
®system has entered a
tamper mode. If the vehicle fails to start, seePasslock®
on page 2-19.
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, seeContent Theft-Deterrent on page 2-17for
additional information regarding the SECURITY light.
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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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If the current tuned station does not broadcast traffic
announcements, press this button and the radio
will seek to a station that does. When the radionds a
station that broadcasts traffic announcements, it will
stop. Brackets will be displayed around TRAF and when
a traffic announcement comes on the tuned radio
station you will hear it. If no station is found, NO
TRAFFIC will appear on the display.
Traffic Interrupt Feature:Your radio can interrupt the
play of a CD. Press the TRAF button. The radio will
seek to a station that broadcasts traffic announcements.
When the radionds a station that broadcasts traffic
announcements, it will stop. Brackets around TRAF will
appear on the display. When a traffic announcement
comes on the station that was found, you will hear
it. When the traffic announcement is over, the radio will
resume play of the CD. If no station is found, NO
TRAFFIC will appear on the display.Playing a Compact Disc
If an error appears on the display, see“Compact Disc
Messages”later in this section.
LOAD CD
Z:Press the LOAD side of this button to
load CDs into the compact disc player. This compact
disc player will hold up to six discs.
To insert one disc, do the following:
1. Turn the ignition on.
2. Press and release the LOAD side of the LOAD CD
button.
3. Wait for the light, located to the right of the slot, to
turn green.
4. Load a disc. Insert the disc partway into the slot,
label side up. The player will pull the disc in.
When a disc is inserted, the CD symbol will be
displayed. If you select an equalization setting for your
disc, it will be activated each time you play a disc.
If the radio is on or off, the disc will begin to play
automatically.
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To insert multiple discs, do the following:
1. Turn the ignition on.
2. Press and hold the LOAD side of the LOAD CD
button for two seconds.
You will hear a beep and the light, located to the
right of the slot, will begin toash.
3. Once the light stopsashing and turns green, load
a disc. Insert the disc partway into the slot, label
side up. The player will pull the disc in.
Once the disc is loaded, the light will beginashing
again. Once the light stopsashing and turns green
you can load another disc. The disc player takes up
to six discs. Do not try to load more than six.
To load more than one disc but less than six, complete
Steps 1 through 3. When you havenished loading
discs, with the radio on or off, press the LOAD side of
the LOAD CD button to cancel the loading function.
The radio will begin to play the last CD loaded.
When a disc is inserted, the CD symbol will be
displayed. If more than one disc has been loaded, a
number for each disc will be displayed. If you select an
equalization setting for your disc, it will be activated
each time you play a disc.
If the radio is on or off, the last disc loaded will begin to
play automatically.
As each new track starts to play, the track number will
appear on the display.Playing a Specic Loaded
Compact Disc
For every CD loaded, a number will appear on the radio
display. To play a specic CD,rst press the CD AUX
button to start playing a CD. Then press the numbered
pushbutton that corresponds to the CD you want to
play. A small bar will appear under the CD number that
is playing, and the track number will appear.
If an error appears on the radio display, see“Compact
Disc Messages”later in this section.
LOAD CD
Z(Eject):Pressing the CD eject side of
this button will eject a single disc or multiple discs.
To eject the disc that is currently playing, press
and release this button. To eject multiple discs, press
and hold this button for two seconds. You will hear
a beep and the light willash to let you know when a
disc is being ejected.
REMOVE CD will be displayed. You can now remove
the disc. If the disc is not removed, after 25 seconds, the
disc will be automatically pulled back into the receiver.
If you try to push the disc back into the receiver,
before the 25 second time period is complete, the
receiver will sense an error and will try to eject the disc
several times before stopping.
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Compact Disc Messages
CHECK CD:If this message appears on the radio
display, it could be due to one of the following reasons:
You’re driving on a very rough road. When the
road becomes smoother, the disc should play.
The disc is dirty, scratched, wet or upside down.
The air is very humid. If so, wait about an hour
and try again.
If the CD is not playing correctly, for any other reason,
try a known good CD.
If any error occurs repeatedly or if an error can’tbe
corrected, contact your dealer. If your radio displays an
error message, write it down and provide it to your
dealer when reporting the problem.
Theft-Deterrent Feature
(Non-RDS Radios)
THEFTLOCK®is designed to discourage theft of your
radio. The feature works automatically by learning
a portion of the Vehicle Identication Number (VIN).
If the radio is moved to a different vehicle, it will
not operate and LOC will be displayed.
With THEFTLOCK
®activated, your radio will not
operate if stolen.
Theft-Deterrent Feature
(RDS Radios)
THEFTLOCK®is designed to discourage theft of your
radio. The feature works automatically by learning
a portion of the Vehicle Identication Number (VIN).
If the radio is moved to a different vehicle, it will
not operate and LOCKED will be displayed.
When the radio and vehicle are turned off, the blinking
red light indicates that THEFTLOCK
®is armed.
With THEFTLOCK®activated, your radio will not
operate if stolen.
Understanding Radio Reception
AM
The range for most AM stations is greater than for FM,
especially at night. The longer range, however, can
cause stations to interfere with each other. AM can pick
up noise from things like storms and power lines. Try
reducing the treble to reduce this noise if you ever get it.
FM
FM stereo will give you the best sound, but FM signals
will reach only about 10 to 40 miles (16 to 65 km).
Tall buildings or hills can interfere with FM signals,
causing the sound to come and go.
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Care of Your Cassette Tape Player
A tape player that is not cleaned regularly can cause
reduced sound quality, ruined cassettes or a damaged
mechanism. Cassette tapes should be stored in their
cases away from contaminants, direct sunlight and
extreme heat. If they aren’t, they may not operate
properly or may cause failure of the tape player.
Your tape player should be cleaned regularly after every
50 hours of use. Your radio may display CLEAN to
indicate that you have used your tape player for
50 hours without resetting the tape clean timer. If this
message appears on the display, your cassette
tape player needs to be cleaned. It will still play tapes,
but you should clean it as soon as possible to
prevent damage to your tapes and player. If you notice
a reduction in sound quality, try a known good
cassette to see if the tape or the tape player is at fault.
If this other cassette has no improvement in sound
quality, clean the tape player.
For best results, use a scrubbing action, non-abrasive
cleaning cassette with pads which scrub the tape
head as the hubs of the cleaner cassette turn. The
recommended cleaning cassette is available through
your dealership.The broken tape detection feature of your cassette tape
player may identify the cleaning cassette as a
damaged tape, in error. To prevent the cleaning cassette
from being ejected, use the following steps:
1. Turn the ignition on.
2. Turn the radio off.
3. Press and hold the TAPE CD button forve
seconds. READY will appear on the display and a
cassette symbol willash forve seconds.
4. Insert the scrubbing action cleaning cassette.
5. Eject the cleaning cassette after the manufacturer’s
recommended cleaning time.
After the cleaning cassette is ejected, the broken tape
detection feature will be active again.
You may also choose a non-scrubbing action, wet-type
cleaner which uses a cassette with a fabric belt to
clean the tape head. This type of cleaning cassette will
not eject on its own. A non-scrubbing action cleaner
may not clean as thoroughly as the scrubbing type
cleaner. The use of a non-scrubbing action, dry-type
cleaning cassette is not recommended.
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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.
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