2002 CHEVROLET C3500 HD lock

3-2
Comfort Controls
Heater Control System
Fan Knob
The knob located on the left side of the heating system
control panel regulates the fan speed. The knob has four
positions. To increase airflow, turn the knob toward HI.
To decrease airflow, turn it toward LO. To turn the fan
off, turn the knob to OFF.
Temperature Knob
The middle knob on the control panel lets you select the
temperature of the air flowing into the passenger area
of your vehicle.This knob will allow you to adjust the air temperature
independently of the fan knob settings. Turn the
knob clockwise, toward the red area, for warmer air.
Turn the knob counterclockwise, toward the blue area,
for cooler air.
Mode Knob
The right knob on the control panel allows you to
choose the direction of air delivery. The knob can be
placed in any position between two mode settings to
blend the flow of air.
(Vent): This setting directs air through the
instrument panel outlets.
(Bi-Level): This setting divides airflow
between the floor outlets and instrument panel outlets.
(Floor): This setting directs air through the
floor outlets.
(Blend): This setting directs air to the floor
outlets and toward the windshield.
(Defrost): This setting directs air toward
the windshield.

3-3 Heater and Air Conditioning Control
System (If Equipped)
Fan Knob
The knob located on the left side of the heating system
control panel regulates the fan speed. The knob has
four speed positions. To increase airflow, turn the knob
toward HI. To decrease airflow, turn it toward LO.
To turn the fan off, turn the knob to OFF. If you have
the air conditioner on, turning the fan knob to OFF also
turns off the A/C compressor.
With the fan knob in OFF while driving, the airflow will
be directed to the floor air outlets. The mode knob will
not redirect airflow to other selected outlet positions.
This is normal operation for OFF.Temperature Knob
The middle knob on the control panel lets you select the
relative temperature of the air flowing into the passenger
area of your vehicle. This knob will allow you to adjust
the relative air temperature independently of the fan and
knob settings. Turn the knob clockwise, toward the red
area, for warmer air. Turn the knob counterclockwise,
toward the blue area, for cooler air.
Mode Knob
The right knob on the control panel allows you to
choose the direction of air delivery. The knob can be
placed in any position between two mode settings to
blend the flow of air.(Vent): This setting directs air through the
instrument panel outlets.
(Bi-Level): This setting divides airflow between
the floor air outlets and instrument panel outlets.
(Floor): This setting directs air through the
floor outlets.
(Blend): This setting directs air to the floor
outlets and toward the windshield.
(Defrost): This setting directs air toward
the windshield.

3-4 Air Conditioning
On hot days, open the windows long enough to let hot
air inside escape. This reduces the time it takes for your
vehicle to cool down. Then keep your windows closed
for the air conditioner to work its best.
A/C (Air Conditioning): Press this button to turn the
air conditioning compressor on and off. The system will
cool and dehumidify the air inside the vehicle when the
A/C light is on.
Air conditioning will be automatically disabled when
the outside temperature drops below a level at which
air conditioning is ineffective.
With the A/C on, turn the temperature knob to MAX
for maximum cooling. This setting also puts the system
in the recirculation mode and helps to maximize your
air conditioner's performance and your vehicle's
fuel economy.
(Recirculation): Pressing the recirculation
button limits the amount of outside dust and odors
entering your vehicle. This button will be automatically
disabled anytime the mode knob is turned to blend or
defrost mode. (The recirculation indicator light will
come on even though the recirculation button is not
selected). This setting also cools the air the fastest.After the vehicle's interior reaches a comfortable
temperature, turn the temperature knob clockwise, to
place the air conditioning system in the normal mode.
Heating
The heater works best if you keep your windows closed
while using it. On cold days, use the floor or bi
-level
setting with the temperature knob in the red area.
If you use the engine coolant heater before starting your
engine in cold weather, 20
F (
-8
C) or lower, your
heating system will produce warmer air faster, to heat
the passenger compartment in cold weather.
The use of an engine coolant heater also reduces the
time it takes for the engine to reach normal operating
temperature, and shortens the time it takes the heater to
reach full output. For more information, see ªEngine
Coolant Heaterº in the Index.
Defogging and Defrosting
On cool, humid days, use blend to keep the windshield
and side windows clear. Use defrost to remove fog or
ice from the windshield in extremely humid or cold
conditions. Use defrost with the temperature knob
toward the red area and the fan control toward HI.

3-6
Ventilation Tips

Keep the hood and front air inlet free of ice, snow or
any other obstruction (such as leaves). The heater
and defroster will work far better, reducing the
chance of fogging the inside of your windows.

When you enter a vehicle in cold weather, turn
the fan to HI for a few moments before driving.
This helps clear the intake ducts of snow and
moisture, and reduces the chance of fogging the
inside of your windows.

Keep the air path under the front seats clear of
objects. This helps air to circulate throughout
your vehicle.

The use of hood air deflectors may adversely
affect the performance of the heating and air
conditioning system.Audio Systems
Your audio system has been designed to operate easily
and give years of listening pleasure. You will get the
most enjoyment out of it if you acquaint yourself with it
first. 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.
Setting the Clock for Systems with the
SET Button
Press SET. Within five seconds, press and hold the right
SEEK arrow until the correct minute appears on the
display. Press and hold the left SEEK arrow until the
correct hour appears on the display.
Setting the Clock for Systems with HR
and MN Buttons
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 clock 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.

3-7 AM-FM Stereo
Playing the Radio
Power: Turn the VOLUME knob clockwise to turn the
system on and counterclockwise to turn the system off.
VOLUME: Turn this knob clockwise to increase
volume. Turn it counterclockwise to decrease volume.
RECALL: Pressing this knob will display the station
being played or it will display the clock. Clock display
is available with the ignition turned off.Finding a Station
AM
-FM: Press this knob to switch between AM,
FM1 and FM2. The display shows your selection.
TUNE: Turn this knob to tune in radio stations.
SEEK: Press the right or left arrow to seek to
the next or previous station and stay there.
SCAN: Press both SCAN arrows. SCAN will
appear on the display. The radio will scan to the next
station, play for a few seconds, then scan to the next
station. Press the RECALL knob or both SCAN arrows
to stop scanning.
Setting Preset Stations
The four numbered pushbuttons let you return to
your favorite stations. You can set up to 21 stations
(seven AM, seven FM1 and seven 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 SET. SET will appear on the display.

3-9 AM-FM Stereo with Cassette Tape Player
(If Equipped)
Playing the Radio
Power: Turn the VOLUME knob to turn the system
on and off.
VOLUME: Turn this knob clockwise to increase
volume. Turn it counterclockwise to decrease volume.
RECALL: Press this knob to display the station being
played or to display the clock. Clock display is available
with the ignition turned off.Finding a Station
AM
-FM: Press this knob to switch between AM,
FM1 and FM2.
TUNE: Turn this knob to tune in radio stations.
 SEEK
: Press the right or left arrow to seek
to the next or previous station and stay there.
PSCAN: To scan preset stations, press both SEEK
buttons. The radio will go to the first preset station
stored on the pushbutton, play for a few seconds,
then go on to the next preset station. Press either
SEEK button or RECALL to stop scanning through
the preset stations.
Setting Preset Stations
The four numbered pushbuttons let you return to
your favorite stations. You can set up to 21 stations
(seven AM, seven FM1 and seven 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 SET. SET will appear on the display.

3-12 AM-FM Stereo with Cassette Tape Player
and Automatic Tone Control (If Equipped)
Playing the Radio
PWR (Power): Press this knob to turn the system
on and off.
VOL (Volume): Turn this knob clockwise to increase
volume. Turn it counterclockwise to decrease volume.
The knob is capable of being turned continuously.RECALL: Pressing this button will display the station
being played or it will display the clock. Clock display
is available with the ignition turned off.
SCV (Speed
-Compensated Volume): 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. Each notch on the
control ring allows for more volume compensation
at faster vehicle speeds. Then, as you drive, SCV
automatically increases the volume, as necessary, to
overcome noise at any 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.
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.

3-14
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 to adjust sound to 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.