lock GMC SONOMA 2003 Workshop Manual

To adjust bass or treble to the middle position, select
BAS or TRE. Then press and hold AUDIO for more than
two seconds until you hear a beep. B and a zero or T
and a zero will appear on the display.
To adjust both tone controls and both speaker controls
to the middle position, end out of audio by waiting
for the display to change to the time display. Then press
and hold AUDIO for more than two seconds until you
hear a beep. CEN will appear on the display.
Adjusting the Speakers (Balance/Fade)
AUDIO:To adjust the balance between the right
and the left speakers, press and release AUDIO until
BAL appears on the display. Then press and hold the up
or the down arrow to move the sound toward the right
or the left speakers.
To adjust the fade between the front and the rear
speakers, press and release AUDIO until FAD appears
on the display. Then press and hold the up or the
down arrow to move the sound toward the front or the
rear speakers.To adjust balance or fade to the middle position, select
BAL or FAD. Then press and hold AUDIO for more
than two seconds until you hear a beep. L and a zero
or F and a zero will appear on the display.
To adjust both tone controls and both speaker controls
to the middle position, end out of audio by waiting
for the display to change to the time display. Then press
and hold AUDIO for more than two seconds until you
hear a beep. CEN will appear on the display.
Fade may not be available if you have a regular cab
model.Radio Messages
CAL (Calibrated):Your audio system has been
calibrated for your vehicle from the factory. If CAL
appears on the display it means that your radio has not
been congured properly for your vehicle and must
be returned to the dealership for service.
LOC (Locked):This message is displayed when the
Theftlock
®system has locked up. Your vehicle must be
returned to the dealership for service.
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Radio Messages
CAL ERR (Calibration Error):This message is
displayed when the radio has not been calibrated
properly for the vehicle. You must return to the
dealership for service.
LOCKED:This message is displayed when the
THEFTLOCK
®system has locked up. You must return
to the dealership for service.
Playing a Compact Disc
Insert a disc partway into the slot, label side up. The
player will pull it in and the disc should begin playing.
The display will show the CD symbol. If you want
to insert a compact disc with the ignition off,rst press
TUNE or EJT.
If an error appears on the display, see“Compact Disc
Messages”later in this section.
1 PREV (Previous):Press this pushbutton to go to the
previous track if the current track has been playing
for less than eight seconds. If pressed when the current
track has been playing for more than eight seconds,
it will go to the beginning of the current track. TRACK
and the track number will appear on the display. If
you hold this pushbutton or press it more than once,
the player will continue moving back through the disc.2 NEXT:Press this pushbutton to go to the next
track. TRACK and the track number will appear on the
display. If you hold this pushbutton or press it more
than once, the player will continue moving forward
through the disc.
3 REV (Reverse):Press and hold this pushbutton to
reverse quickly within a track. Press and hold this
pushbutton for less than two seconds to reverse at six
times the normal playing speed. Press and hold it
for more than two seconds to reverse at 17 times the
normal playing speed. Release it to play the passage.
The display will show ET and the elapsed time.
4 FWD (Forward):Press and hold this pushbutton to
advance quickly within a track. Press and hold this
pushbutton for less than two seconds to advance at six
times the normal playing speed. Press and hold it for
more than two seconds to advance at 17 times the
normal playing speed. Release it to play the passage.
The display will show ET and the elapsed time.
6 RDM (Random):Press this pushbutton to hear the
tracks in random, rather than sequential, order.
RDM ON will appear on the display. RDM T and the
track number will appear on the display when each
track starts to play. Press this pushbutton again to
turn off random play. RDM OFF will appear on
the display.
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When a traffic announcement comes on the current
station or on a related network station, you will hear it,
even if the volume is muted or a compact disc is
playing. The traffic symbol and TRAF will appear on the
display while the announcement plays. If the compact
disc player was being used, play will stop during
the announcement.
Traffic Interrupt Feature:Your radio can interrupt the
play of a cassette or 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.
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 cassette or CD. If
no station is found, NO TRAF will appear on the display.
Radio Messages
CAL ERR (Calibration Error):This message is
displayed when the radio has not been calibrated
properly for the vehicle. You must return to the
dealership for service.
LOCKED:This message is displayed when the
THEFTLOCK
®system has locked up. You must return
to the dealership for service.
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. The longer side with the tape visible
should face to the right. If the ignition is on, but the radio
is off, the tape can be inserted and will begin playing.
A tape symbol is shown on the display whenever a tape
is inserted. If you hear nothing but a garbled sound,
the tape may not be in squarely. Press EJT to remove
the tape and start over.
While the tape is playing, use the VOL, AUDIO and
SEEK controls just as you do for the radio. The display
will show TAPE and an arrow showing which side of
the tape is playing.
If you want to insert a tape while the ignition is off,rst
press DISP or EJT.
If an error appears on the display, see“Cassette Tape
Messages”later in this section.
1 PREV (Previous):Your tape must have at least three
seconds of silence between each selection for previous
to work. Press this pushbutton to go to the previous
selection on the tape if the current selection has been
playing for less than three seconds. If pressed when the
current selection has been playing from 3 to 13 seconds,
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Cassette Tape Messages
CHK TAPE (Check Tape):If CHK TAPE appears on
the radio display, the tape won’t play because of one of
the following errors.
The tape is tight and the player can’t turn the tape
hubs. Remove the tape. Hold the tape with the
open end down and try to turn the right hub
counterclockwise with a pencil. Turn the tape over
and repeat. If the hubs do not turn easily, your
tape may be damaged and should not be used in
the player. Try a new tape to make sure your player
is working properly.
The tape is broken. Try a new tape.
The tape is wrapped around the tape head. Attempt
to get the cassette out. Try a new tape.
CLEAN:If this message appears on the display, the
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 the tapes and player. SeeCare
of Your Cassette Tape Player on page 3-68.
If any error occurs repeatedly or if an error can’tbe
corrected, contact your dealer.
Playing a Compact Disc
Insert a disc partway into the slot, label side up. The
player will pull it in and the disc should begin playing.
The display will show the CD symbol. If you want
to insert a compact disc with the ignition off,rst press
DISP or EJT.
If an error appears on the display, see“Compact Disc
Messages”later in this section.
1 PREV (Previous):Press this pushbutton to go to the
previous track if the current track has been playing
for less than eight seconds. If pressed when the current
track has been playing for more than eight seconds,
it will go to the beginning of the current track. TRACK
and the track number will appear on the display. If
you hold this pushbutton or press it more than once, the
player will continue moving back through the disc.
2 NEXT:Press this pushbutton to go to the next track.
TRACK and the track number will appear on the
display. If you hold this pushbutton or press it more than
once, the player will continue moving forward through
the disc.
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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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Your Driving, the Road, and Your Vehicle..........4-2
Defensive Driving...........................................4-2
Drunken Driving.............................................4-2
Control of a Vehicle........................................4-5
Braking.........................................................4-5
Locking Rear Axle..........................................4-7
Steering........................................................4-8
Off-Road Recovery.......................................4-10
Passing.......................................................4-10
Loss of Control.............................................4-12
Off-Road Driving with Your Four-Wheel-Drive
Vehicle....................................................4-13
Driving at Night............................................4-27
Driving in Rain and on Wet Roads
..................4-28
City Driving
..................................................4-31Freeway Driving...........................................4-32
Before Leaving on a Long Trip.......................4-33
Highway Hypnosis........................................4-34
Hill and Mountain Roads................................4-34
Winter Driving..............................................4-36
If You Are Stuck: In Sand, Mud,
Ice or Snow..............................................4-40
Towing..........................................................4-42
Towing Your Vehicle.....................................4-42
Recreational Vehicle Towing...........................4-42
Loading Your Vehicle....................................4-46
Truck-Camper Loading Information..................4-48
Trailer Recommendations...............................4-50
Pickup Conversion to Chassis Cab..................4-50
Towing a Trailer...........................................4-51
Section 4 Driving Your Vehicle
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If you keep pace with the traffic and allow realistic
following distances, you will eliminate a lot of
unnecessary braking. That means better braking and
longer brake life.
If your engine ever stops while you’re driving, brake
normally but don’t pump your brakes. If you do,
the pedal may get harder to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer to stop and
the brake pedal will be harder to push.
Anti-lock Brake System
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there’s a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-28.Let’s say the road is wet and you’re driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here’s what
happens with ABS:
A computer senses that wheels are slowing down. If
one of the wheels is about to stop rolling, the computer
will separately work the brakes at each front wheel
and at both rear wheels.
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The anti-lock system can change the brake pressure
faster than any driver could. The computer is
programmed to make the most of available tire and road
conditions. This can help you steer around the obstacle
while braking hard.
As you brake, your computer keeps receiving updates
on wheel speed and controls braking pressure
accordingly.Remember: Anti-lock doesn’t change the time you need
to get your foot up to the brake pedal or always
decrease stopping distance. If you get too close to the
vehicle in front of you, you won’t have time to apply
your brakes if that vehicle suddenly slows or stops.
Always leave enough room up ahead to stop, even
though you have anti-lock brakes.
Using Anti-Lock
Don’t pump the brakes. Just hold the brake pedal down
rmly and let anti-lock work for you. You may feel the
brakes vibrate, or you may notice some noise, but this
is normal.
Braking in Emergencies
With anti-lock, you can steer and brake at the same
time. In many emergencies, steering can help you more
than even the very best braking.
Locking Rear Axle
If your vehicle has this feature, your locking rear axle
can give you additional traction on snow, mud, ice, sand
or gravel. It works like a standard axle most of the
time, but when one of the rear wheels has no traction
and the other does, this feature will allow the wheel with
traction to move the vehicle.
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Steering in Emergencies
There are times when steering can be more effective than
braking. For example, you come over a hill andnd a
truck stopped in your lane, or a car suddenly pulls out
from nowhere, or a child darts out from between parked
cars and stops right in front of you. You can avoid these
problems by braking—if you can stop in time. But
sometimes you can’t; there isn’t room. That’s the time for
evasive action—steering around the problem.
Your vehicle can perform very well in emergencies like
these. First apply your brakes.
SeeBraking on page 4-5. It is better to remove as much
speed as you can from a possible collision. Then steer
around the problem, to the left or right depending on the
space available.An emergency like this requires close attention and a
quick decision. If you are holding the steering wheel at
the recommended 9 and 3 o’clock positions, you
can turn it a full 180 degrees very quickly without
removing either hand. But you have to act fast, steer
quickly, and just as quickly straighten the wheel
once you have avoided the object.
The fact that such emergency situations are always
possible is a good reason to practice defensive driving
at all times and wear safety belts properly.
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Loss of Control
Let’s review what driving experts say about what happens
when the three control systems (brakes, steering and
acceleration) don’t have enough friction where the tires
meet the road to do what the driver has asked.
In any emergency, don’t give up. Keep trying to steer
and constantly seek an escape route or area of
less danger.
Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking reasonable
care suited to existing conditions, and by not
“overdriving”those conditions. But skids are always
possible.
The three types of skids correspond to your vehicle’s
three control systems. In the braking skid, your wheels
aren’t rolling. In the steering or cornering skid, too much
speed or steering in a curve causes tires to slip and lose
cornering force. And in the acceleration skid, too much
throttle causes the driving wheels to spin.
A cornering skid is best handled by easing your foot off
the accelerator pedal.If your vehicle starts to slide, ease your foot off the
accelerator pedal and quickly steer the way you want
the vehicle to go. If you start steering quickly enough,
your vehicle may straighten out. Always be ready
for a second skid if it occurs.
Of course, traction is reduced when water, snow, ice,
gravel or other material is on the road. For safety, you’ll
want to slow down and adjust your driving to these
conditions. It is important to slow down on slippery
surfaces because stopping distance will be longer and
vehicle control more limited.
While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration
or braking (including engine braking by shifting to a
lower gear). Any sudden changes could cause the tires
to slide. You may not realize the surface is slippery
until your vehicle is skidding. Learn to recognize warning
clues—such as enough water, ice or packed snow
on the road to make a“mirrored surface”—and slow
down when you have any doubt.
Remember: Any anti-lock brake system (ABS) helps
avoid only the braking skid.
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