2002 CHEVROLET C3500 HD heating

2-56 Engine Coolant Temperature Gage
This gage shows the engine
coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210
F (100
C) or less. If you are pulling a
load or going up hills, it is normal for the temperature to
fluctuate and approach the 260
F (125
C) mark. If the
gage reaches the 260
F (125
C) mark, it indicates that
the cooling system is working beyond its capacity.
See ªEngine Overheatingº in the Index.
Malfunction Indicator Lamp (Service
Engine Soon Light in the United States
or Check Engine Light in Canada)
(Gasoline Engine)
United States Canada
Your vehicle is equipped with a computer which
monitors operation of the fuel, ignition and emission
control systems.

2-60 Reduced Engine Power
The REDUCED ENGINE
POWER light will come
on when the cooling system
temperature gets too hot
and the engine further
enters the engine coolant
protection mode.
See ªEngine Overheatingº in the Index for
further information.
Oil Pressure Gage
United States Canada
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).

3-
3-1
Section 3 Comfort Controls and Audio Systems
In this section, you'll find out how to operate the comfort control and audio systems offered with your vehicle.
Be sure to read about the particular systems supplied with your vehicle.
3
-2 Comfort Controls
3
-4 Air Conditioning
3
-4 Heating
3
-4 Defogging and Defrosting
3
-5 Ventilation System
3
-6 Audio Systems
3
-6 Setting the Clock For Systems with the
SET Button
3
-6 Setting the Clock For Systems with the
HR and MN Button
3
-7AM-FM Stereo
3
-9AM-FM Stereo with Cassette Tape Player
(If Equipped)3
-12 AM-FM Stereo with Cassette Tape Player
and Automatic Tone Control (If Equipped)
3
-17 AM-FM Stereo with Compact Disc Player
and Automatic Tone Control (If Equipped)
3
-22 Theft-Deterrent Feature (If Equipped)
3
-24 Understanding Radio Reception
3
-24 Tips About Your Audio System
3
-25 Care of Your Cassette Tape Player
3
-26 Care of Your Compact Discs
3
-26 Care of Your Compact Disc Player
3
-26 Fixed Mast Antenna

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.

3-5 Ventilation System
For mild outside temperatures when little heating
or cooling is needed, use vent to direct outside air
through your vehicle. Air will flow through the
instrument panel outlets.
Your vehicle's ventilation system supplies outside
air to the inside of your vehicle when it is moving.
With the side windows closed, air will flow into the
front air inlet grilles, through the vehicle, and out the
air exhaust valves.
Outside air will also enter the vehicle when the heater or
the air conditioning fan is running, unless you have the
recirculation button pushed in. For more information on
the recirculation button, see ªAir Conditioningº earlier
in this section.
Your vehicle has air outlets in the center and on the sides
of your instrument panel. You can move the outlets from
side
-to-side or up and down to direct the flow of air, or
close the outlets altogether. When you close an outlet,
it will increase the flow of air coming out of any outlets
that are open. These outlets do not completely shut off
airflow when in the closed position.

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.