lock GMC SONOMA 2000 Workshop Manual

3-13
SCAN: Press and hold SEEK for two seconds until
SCAN appears on the display. SCAN allows you to
listen to stations for a few seconds. The receiver will
continue to scan and momentarily stop at each station
until you press the button again. The sound will mute
while scanning.
PUSHBUTTONS: 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). Just:
1. Turn the radio on.
2. Press AM
-FM to select the band.
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 button, the
station you set will return and the tone you selected
will be automatically selected for that button.
6. Repeat the steps for each pushbutton.P.SCAN: The preset scan button lets you scan through
your favorite stations stored on your pushbuttons.
Select either the AM, FM1 or FM2 mode and then press
P. SCAN. It will scan through each station stored on your
pushbuttons and stop for a few seconds before continuing
to scan through all of the pushbuttons. Press P. SCAN
again or one of the pushbuttons to stop scanning to listen
to a specific preset station. P. SCAN will light up on the
display while in this mode. If one of the stations stored on
a pushbutton is too weak for the location you are in, the
radio display will show the channel number (P1
-P6) for
several seconds before advancing to the next preset station.
Setting the Tone
BASS: Press lightly on this knob to release it from its
stored position. Turn the knob clockwise to increase bass
and counterclockwise to decrease bass. When the BASS
control is rotated, the AUTO TONE display will go blank.
TREB: Press lightly on this knob to release it from its
stored position. Turn the knob clockwise to increase
treble and counterclockwise to decrease treble. When
the TREB control is rotated, the AUTO TONE display
will go blank. 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.

3-14
AUTO TONE: Press this button to select among the
six preset equalization settings and tailor the sound to the
music or voice being heard. Each time you press the
button, the selection will switch to one of the preset
settings of CLASSIC, NEWS, ROCK, POP, C/W
(Country/Western) or JAZZ. To return to the manual
mode, press and release this button until the AUTO TONE
display goes blank. This will return the tone adjustment to
the BASS and TREB controls. If a BASS or TREB
control is rotated, the AUTO TONE display will go blank.
Use PUSHBUTTONS to program AUTO TONE.
Adjusting the Speakers
BAL: Press lightly on this knob to release it from its
stored position. Turn the control 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 lightly on this knob to release it from its
stored position. Turn the control 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.
PREV (1): Press the PREV button or the SEEK left
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 during the SEEK operation.
PROG (2): Press this button to switch from one side of
the tape to the other.

3-16
CD Adapter Kits
It is possible to use a portable CD player adapter kit
with your cassette tape player after activating the bypass
feature on your tape player.
To activate the bypass feature, use the following steps:
1. Turn the ignition to RUN or ACCESSORY.
2. Turn the radio off.
3. Press and hold the TAPE AUX button for five
seconds. The tape symbol on the display will flash
for two seconds, indicating the feature is active.
4. Insert the adapter into the cassette slot. It will power
up the radio and begin playing.
This override routine will remain active until EJECT
is pressed.AM-FM Stereo with Compact Disc Player
and Automatic Tone Control (If Equipped)
Playing the Radio
PWR
-VOL: Press this knob to turn the system on and
off. To increase volume, turn this knob clockwise. Turn
it counterclockwise to decrease volume. The knob is
capable of rotating continuously.
RECALL: Display the time with the ignition off by
pressing this button. When the radio is playing, press
this button to recall the station frequency.

3-17
SCV: Your system has a feature called
Speed
-Compensated Volume (SCV). 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. Then, as you drive,
SCV automatically increases the volume, as necessary,
to overcome noise at any particular 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. Each notch on the control ring allows for
more volume compensation at faster vehicle speeds.
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 arrow to tune to the next higher
station and the left arrow to tune to the next lower station
and stay there. The sound will mute while seeking.SCAN: Press and hold SEEK for two seconds until
SCAN appears on the display. SCAN allows you to
listen to stations for a few seconds. The receiver will
continue to scan and momentarily stop at each station
until you press the button again. The sound will mute
while scanning.
PUSHBUTTONS: 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). Just:
1. Turn the radio on.
2. Press AM
-FM to select the band.
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 button, the
station you set will return and the tone you selected
will be automatically selected for that button.
6. Repeat the steps for each pushbutton.

3-18
P.SCAN: The preset scan button lets you scan through
your favorite stations stored on your pushbuttons.
Select either the AM, FM1 or FM2 mode and then press
P.SCAN. It will scan through each station stored on your
pushbuttons and stop for a few seconds before continuing
to scan through all of the pushbuttons. Press P.SCAN
again or one of the pushbuttons to stop scanning to listen
to a specific stored station. P.SCAN will light up on the
display while in this mode. If one of the stations stored on
a pushbutton is too weak for the location you are in, the
radio display will show the channel number (P1
-P6) for
several seconds before advancing to the next preset station.
Setting the Tone
BASS: Press lightly on this knob to release it from its
stored position. Turn the knob clockwise to increase bass
and counterclockwise to decrease bass. When the BASS
control is rotated, the AUTO TONE display will go blank.
TREB: Press lightly on this knob to release it from its
stored position. Turn the knob clockwise to increase
treble and counterclockwise to decrease treble. When
the TREB control is rotated, the AUTO TONE display
will go blank. 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: Press this button to select among the
six preset equalization settings and tailor the sound to the
music or voice being heard. Each time you press the
button, the selection will switch to one of the preset
settings of CLASSIC, NEWS, ROCK, POP, C/W
(Country/Western) or JAZZ. To return to the manual
mode, press and release this button until the AUTO TONE
display goes blank. This will return the tone adjustment to
the BASS and TREB controls. If a BASS or TREB
control is rotated, the AUTO TONE display will go blank.
Use PUSHBUTTONS to program AUTO TONE.
Adjusting the Speakers
BAL: Press lightly on this knob to release it from its
stored position. Turn the control 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 lightly on this knob to release it from its
stored position. Turn the control 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.

3-22 Theft-Deterrent Feature (If Equipped)
THEFTLOCK
is designed to discourage theft of your
radio. It works by using a secret code to disable all radio
functions whenever battery power is removed.
The THEFTLOCK feature for the radio may be used or
ignored. If ignored, the system plays normally and the
radio is not protected by the feature. If THEFTLOCK is
activated, your radio will not operate if stolen.
When THEFTLOCK is activated, the radio will display
LOC to indicate a locked condition anytime battery
power has been interrupted. If your battery loses power
for any reason, you must unlock the radio with the secret
code before it will operate.
Activating the Theft
-Deterrent Feature
The instructions which follow explain how to enter your
secret code to activate the THEFTLOCK system. It is
recommended that you read through all nine steps
before starting the procedure.
If you allow more than 15 seconds to elapse between
any steps, the radio automatically reverts to time and
you must start the procedure over at Step 4.1. Write down any three or four
-digit number
from 000 to 1999 and keep it in a safe place separate
from the vehicle.
2. Turn the ignition to ACCESSORY or RUN.
3. Turn the radio off.
4. Press the 1 and 4 buttons together. Hold them down
until
--- shows on the display. Next you will use the
secret code number which you have written down.
5. Press MN and 000 will appear on the display.
6. Press MN again to make the last two digits agree
with your code.
7. Press HR to make the first one or two digits agree
with your code.
8. Press AM
-FM after you have confirmed that the
code matches the secret code you have written down.
The display will show REP to let you know that you
need to repeat Steps 5 through 7 to confirm your
secret code.
9. Press AM
-FM and this time the display will show
SEC to let you know that your radio is secure. The
LED indicator by the volume control will begin
flashing when the ignition is turned off.

3-23
Unlocking the Theft-Deterrent Feature After a
Power Loss
Enter your secret code as follows; pause no more than
15 seconds between steps:
1. Turn the ignition on. LOC will appear on the display.
2. Press MN and 000 will appear on the display.
3. Press MN again to make the last two digits agree
with your code.
4. Press HR to make the first one or two digits agree
with your code.
5. Press AM
-FM after you have confirmed that the
code matches the secret code you have written down.
The display will show SEC, indicating the radio is
now operable and secure.
If you enter the wrong code eight times, INOP will
appear on the display. You will have to wait an hour
with the ignition on before you can try again. When you
try again, you will only have three chances to enter the
correct code before INOP appears.
If you lose or forget your code, contact your dealer.Disabling the Theft
-Deterrent Feature
Enter your secret code as follows; pause no more than
15 seconds between steps:
1. Turn the ignition to ACCESSORY or RUN.
2. Turn the radio off.
3. Press the 1 and 4 buttons together. Hold them down
until SEC shows on the display.
4. Press MN and 000 will appear on the display.
5. Press MN again to make the last two digits agree
with your code.
6. Press HR to make the first one or two digits agree
with your code.
7. Press AM
-FM after you have confirmed that the
code matches the secret code you have written down.
The display will show
---, indicating that the radio is
no longer secured.
If the code entered is incorrect, SEC will appear on the
display. The radio will remain secured until the correct
code is entered.
When battery power is removed and later applied to a
secured radio, the radio won't turn on and LOC will
appear on the display.

3-24
To unlock a secured radio, see ªUnlocking the
Theft
-Deterrent Feature After a Power Lossº earlier in
this section.
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 Stereo
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.
Tips About Your Audio System
Hearing damage from loud noise is almost undetectable
until it is too late. Your hearing can adapt to higher
volumes of sound. Sound that seems normal can be loud
and harmful to your hearing. Take precautions by
adjusting the volume control on your radio to a safe
sound level before your hearing adapts to it.To help avoid hearing loss or damage:

Adjust the volume control to the lowest setting.

Increase volume slowly until you hear comfortably
and clearly.
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 Delco 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.

4-7
Avoid needless heavy braking. Some people drive in
spurts
-- heavy acceleration followed by heavy
braking
-- rather than keeping pace with traffic. This is a
mistake. Your brakes may not have time to cool between
hard stops. Your brakes will wear out much faster if you
do a lot of heavy braking. 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 Brakes (ABS)
Your vehicle has anti-lock brakes (ABS). 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.
See ªAnti
-Lock Brake
System Warning Lightº in
the Index.

4-8
Here's how anti-lock works. Let's say the road is wet.
You're driving safely. Suddenly an animal jumps out in
front of you.
You slam on the brakes. 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.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.
You can steer around the obstacle while braking hard.
As you brake, your computer keeps receiving updates on
wheel speed and controls braking pressure accordingly.