2002 CHEVROLET C3500 HD display

3-19
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 (Treble): 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.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.

3-20
Playing a Compact Disc
Insert a disc partway into the slot, label side up.
The player will pull it in. Wait a few seconds and the
disc should play. CD and a CD symbol will also appear
on the display. Anytime you are playing a CD, the letters
CD will be next to the CD symbol.
If an error appears on the display, see ªCompact Disc
Messagesº later in this section.
1 PREV (Previous): Press this pushbutton to search for
the previous track. If you hold this pushbutton or press it
more than once, the disc will advance further. Sound is
muted in this mode.
2 RDM (Random): Press this pushbutton to play the
tracks on the disc in random order. RANDOM will
appear on the display. Press this pushbutton again to
return to normal play.
3 NEXT: Press this pushbutton to search for the next
track. If you hold this pushbutton or press it more than
once, the disc will advance further. The next track
number will appear on the display. Sound is muted in
this mode.REV 4 (Reverse): Press and hold this pushbutton to
return rapidly to a favorite passage. You will hear the
disc play at high speed while you press this pushbutton.
This allows you to listen and find out when the disc
is at the desired passage. Release this pushbutton to
resume playing.
FWD 6 (Forward): Press and hold this pushbutton
to advance rapidly within a track. You will hear the disc
play at high speed while you press this pushbutton.
This allows you to listen and find out when the disc
is at the desired passage. Release this pushbutton to
resume playing.
SEEK: The right arrow is the same as NEXT, and
a the left arrow is the same as PREV. If the right or left
arrow is held or pressed more than once, the player will
continue moving forward or backward through the disc.
RECALL: Press this button to see what track is playing.
Press it again within five seconds to see how long the
CD has been playing that track. Elapsed time is
displayed in minutes and seconds. The track number
will also appear when a new track begins to play.
Press this button again to return to the time display.

3-21
AM FM: Press this button to listen to the radio when
playing a CD. The CD symbol will still display but the
word CD will be replaced with either AM, FM1 or FM2.
If the radio is turned off, the disc stays in the player and
will resume playing at the point where it stopped.
CD AUX (Auxiliary): Press this button to play a
CD when listening to the radio. When a disc is playing,
the letters CD and the CD symbol will appear on the
display. If the radio is turned off, the disc stays in
the player and will resume playing at the point where
it stopped.
EJECT: Press this button to eject the disc from the
player and play the radio. When the same or a new
disc is inserted, the disc will start playing on track one.
If a compact disc is left sitting in the opening for more
than a few seconds, the player will pull the CD back in.
The radio will continue playing. When the ignition is
off, press this button to load a CD.Compact Disc Messages
ERR (Error): If this message appears and the disc
comes out, it could be for one of the following reasons:

If you're driving on a very rough road. When the
road becomes smooth the disc should play.

If it's very hot. When the temperature returns to
normal, the disc should play.

The disc is upside down.

It is dirty, scratched or wet.

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.
Press RECALL to make ERR go off of the display.
If any error occurs repeatedly or if an error can't be
corrected, contact your dealer.

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 pushbuttons at the same time.
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 knob 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 pushbuttons at the same time.
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.
To unlock a secured radio, see ªUnlocking the
Theft
-Deterrent Feature After a Power Lossº earlier
in this section.

3-25 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 CLN 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 it is the tape or the tape
player at fault. If this other cassette has no improvement
in sound quality, clean the tape player.
The recommended cleaning method for your
cassette tape player is the use of 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 dealer (GM Part No. 12344789).When cleaning the cassette tape player with the
recommended non
-abrasive cleaning cassette, it is
possible that the cassette may eject, because the cut
tape detection feature on your radio may recognize it
as a broken tape. To prevent the cleaning cassette from
being ejected, use the following steps.
If your vehicle is equipped with the AM
-FM Stereo
with Cassette Tape Player do the following:
1. Turn the ignition to RUN or ACCESSORY.
2. Turn the radio on.
3. Insert the scrubbing action cleaning cassette.
4. Within five seconds, press and hold the REV and
FWD buttons at the same time for three seconds.
The tape symbol will flash on the display, showing
that the cut tape detection feature is no longer active.
5. Eject the cleaning cassette after the manufacturer's
recommended cleaning time.
If your vehicle is equipped with the AM
-FM Stereo
with Cassette Tape Player and Automatic Tone Control
do the following:
1. Turn the ignition to RUN or ACCESSORY.
2. Turn the radio off.

3-26
3. Press and hold the TAPE AUX button for five
seconds. The tape symbol on the display will flash
for two seconds.
4. Insert the scrubbing action cleaning cassette.
5. Eject the cleaning cassette after the manufacturer's
recommended cleaning time.
When the cleaning cassette has been ejected, the broken
tape detection feature is 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.
After you clean the player, press and hold the EJECT
button for five seconds to reset the CLN indicator.
The radio will display
--- 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 Compact Discs
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 signal surface when handling
discs. Pick up discs by grasping the outer edges or the
edge of the hole and the outer edge.
Care of Your Compact Disc 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
The fixed 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 every once in a while to be sure the mast is still
tightened to the cowl. If tightening is required, tighten
by hand, then with a wrench one quarter turn.

5-10 Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
REDUCED ENGINE POWER light is displayed, an
overheat protection mode which alternates firing groups
of cylinders helps prevent engine damage. In this mode,
you will notice a loss in power and engine performance.
This operating mode allows your vehicle to be driven
to a safe place in an emergency. Driving extended
miles (km) and/or towing a trailer in the overheat
protection mode should be avoided.
NOTICE:
After driving in the overheated engine protection
operating mode, to avoid engine damage, allow
the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair
the cause of coolant loss and change the oil. See
ªEngine Oilº in the Index.
If Steam Is Coming From Your Engine