2003 CHEVROLET C/K heater

3-2
Comfort Controls
This section tells you how to make your air system work
for you.
With these systems, you can control the heating, cooling
and ventilation in your vehicle.
Heater Controls
If your vehicle does not have air conditioning, the
control panel will look like this.
Fan Knob
The knob on the left side of the control panel regulates
the fan speed. The knob has four speeds. To increase
airflow, turn the knob clockwise. To decrease airflow,
turn it counterclockwise. To turn the fan off, turn the
mode knob on the far right all the way
counterclockwise.Temperature Knob
The middle knob on the control panel is used to adjust
the temperature of the air flowing into the passenger
area of your vehicle.
Turn the knob toward the red area for warmer air. Turn
the knob toward the blue area for cooler air.
Mode Knob
The knob on the right side of the control panel is used to
select the direction of the air flowing into the vehicle.
(Vent): This setting directs air through the
instrument panel vents.
(Bi-Level): This setting divides airflow between
the floor vents and instrument panel vents.
(Floor): This setting directs air through the
floor vents.
(Defog): This setting divides airflow between the
floor vents and windshield.
(Defrost): This setting directs air through the
windshield vents. This setting is used to remove fog or
ice from the windshield.

3-3 Heater/Air Conditioning Controls
(If Equipped)
If your vehicle has air conditioning, the heater/air
conditioning control panel will look like this.
Fan Knob
The knob on the left side of the control panel regulates
the fan speed. It has four speeds.
To increase airflow, turn the knob clockwise. To
decrease airflow, turn it counterclockwise. To turn the
fan off, turn the mode knob on the far right all the way
counterclockwise.Temperature Knob
The middle knob on the control panel is used to adjust
the temperature of the air flowing into the passenger
compartment of your vehicle.
Turn the knob toward the red area for warmer air.
Turn the knob toward the blue area for cooler air.
Mode Knob
The knob on the right side of the control panel is used to
select the direction of the air flowing into the vehicle.
(Maximum Air Conditioning): Turn the right
knob to maximum air conditioning for maximum
cooling. This setting puts the system in the recirculation
mode and helps to maximize your air conditioner's
performance and your vehicle's fuel economy. This
setting also cools the air the fastest. After the vehicle's
interior reaches a comfortable temperature, turn the
knob clockwise to place the air conditioning system in
the regular air conditioning mode.
(Air Conditioning): This setting is used for
normal cooling on hot days. It cools outside air and
directs it through the instrument panel vents.

3-4
(Bi-Level Air Conditioning): This setting divides
airflow between the floor vents and instrument panel
vents. The air conditioning compressor will cycle
continuously in this setting as long as the outside air
temperature is warm enough to activate the compressor.
(Vent): This setting directs air through the
instrument panel vents.
(Floor): This setting directs air through the
floor vents.
(Defog): This setting divides airflow between the
floor vents and windshield vents.
(Defrost): This setting directs air through the
windshield vents. This setting is used to remove fog or
ice from the windshield.
Air Conditioning (If Equipped)
Before using the air conditioning, open the windows to
clear the vehicle of hot air. This reduces the time it takes
for your vehicle to cool down. Then keep your windows
closed for the air conditioner to work at its best.You can use maximum air conditioning with the
temperature knob in the blue area when it's really hot
outside and you need to cool the inside air quickly.
Maximum air conditioning lets in only a little air from
the outside.
If you first use maximum air conditioning, you can then
use regular air conditioning with the temperature knob
in the blue area, as soon as the vehicle has cooled down,
so outside air will be going through your vehicle.
While in maximum air conditioning, regular air
conditioning, bi
-level air conditioning, defog or defrost
mode, you may notice a slight increase or decrease in
engine speed, due to compressor operation. This is
normal because the system is designed to cycle the
compressor on and off to maintain the desired
temperature.
Heating
On cold days, use floor with the temperature knob in the
red area. Outside air will be brought in, heated and
distributed through the floor vents. The heater works
best if you keep your windows closed while using it.
If you use the optional engine coolant heater before
starting your engine, your heating system will produce
warmer air faster to heat the passenger compartment in
cold weather. See ªEngine Coolant Heaterº in the Index.

3-6 Rear Heater (If Equipped)
If your vehicle has a rear
heater, the thumbwheel
for this feature is located
on the headliner.
To increase and decrease the flow of heated air to the
rear floor vents, turn the thumbwheel to the desired
fan speed.
To increase the flow of heated air, turn the thumbwheel
up. To turn the fan off, turn the thumbwheel down.
Ventilation System
For mild outside temperatures when little heating or
cooling is needed, turn the mode knob to vent to direct
outside air through your vehicle. Air will flow through
the instrument panel vents.Your vehicle's flow
-through 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 at the base of the windshield,
through the vehicle and out the rear air exhaust valve.
Outside air will also enter the vehicle when the heater or
the air conditioning compressor is running.
Your vehicle has air vents
near the center and on the
sides of the instrument
panel that allow you to
adjust the direction and the
amount of airflow inside
the vehicle.
Move the thumbwheel on the vent up or down to direct
the airflow. Increase or reduce the amount of airflow by
opening and closing the louvers. The vents can be
moved side
-to-side to direct the airflow.
When you close a vent, it will increase the flow of air
coming out of any vents that are open.

3-7
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 high for a few moments before driving off.
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.Audio Systems
Your audio system has been designed to operate easily
and to 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 Time
Press and hold the HR or MIN arrow for two seconds.
Then press the HR (down) arrow until the correct hour
appears on the display. Press and hold the MIN (up)
arrow until the correct minute appears on the display.
The time may be set with the ignition on or off.

4-29

Tie a red cloth to your mirror arm to alert police that
you've been stopped by the snow.

Put on extra clothing or wrap a blanket around you.
If you have no blankets or extra clothing, make body
insulators from newspapers, burlap bags, rags, floor
mats
-- anything you can wrap around yourself or
tuck under your clothing to keep warm.
You can run the engine to keep warm, but be careful.
CAUTION:
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill
you. You can't see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle if any is blocking
your exhaust pipe. And check around again from
time to time to be sure snow doesn't collect there.
Open a window just a little on the side of the
vehicle that's away from the wind. This will help
keep CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery (or batteries) charged. You will need a
well
-charged battery (or batteries) to restart the vehicle,
and possibly for signaling later on with your headlamps.
Let the heater run for a while.

5-19 If No Steam Is Coming From Your Engine
An overheat warning, along with a low coolant light,
can indicate a serious problem. See ªLow Coolant
Lightº in the Index.
If you get an engine overheat warning with no low
coolant light, but see or hear no steam, the problem may
not be too serious. Sometimes the engine can get a little
too hot when you:

Climb a long hill on a hot day.

Stop after high
-speed driving.

Idle for long periods in traffic.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in neutral while
stopped. If it is safe to do so, pull off the road, shift
to park or neutral and let the engine idle.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.
3. If climbing a hill, downshift to raise engine and
fan speeds.If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning doesn't come back on, you can drive
normally.
If the warning continues and you have not stopped, pull
over, stop, and park your vehicle right away.
If there's still no sign of steam, you can push down the
accelerator until the engine speed is about twice as fast
as normal idle speed for at least three minutes while
you're parked. If you still have the warning, turn off
the engine and get everyone out of the vehicle until it
cools down.
You may decide not to lift the hood but to get service
help right away.

5-20
Cooling System
When you decide it's safe to lift the hood, here's what
you'll see:
A. Engine Fan
B. Coolant Surge Tank
If your vehicle has a Caterpillar diesel engine, see the
Caterpillar

Diesel Engine Operation and Maintenance
Manual provided with your vehicle.If the coolant inside the coolant surge tank is boiling,
don't do anything else until it cools down. The vehicle
should be parked on a level surface.
The coolant level
should be at COLD
FILL or higher. If it
isn't, you may have a
leak at the pressure cap
or in the radiator
hoses, heater hoses,
radiator, water pump
or somewhere else in
the cooling system.