2002 CHEVROLET C3500 HD tow

2-58

Light On Steady -- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center diagnosis and
service may be required.
If the Light Is Flashing
The following may prevent more serious damage to
your vehicle:

Reducing vehicle speed.

Avoiding hard accelerations.

Avoiding steep uphill grades.

If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stops flashing and remains on steady, see ªIf
the Light Is On Steadyº following.
If the light continues to flash, when it is safe to do so,
stop the vehicle. Find a safe place to park your vehicle.
Turn the key off, wait at least 10 seconds and restart the
engine. If the light remains on steady, see ªIf the Light
Is On Steadyº following. If the light is still flashing,
follow the previous steps, and drive the vehicle to your
dealer or qualified service center for service.If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. See ªFilling Your Tankº in the Index. The
diagnostic system can determine if the fuel cap has been
left off or improperly installed. A loose or missing fuel
cap will allow fuel to evaporate into the atmosphere. A
few driving trips with the cap properly installed should
turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.

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.

4-
4-1
Section 4 Your Driving and the Road
Here you'll find information about driving on different kinds of roads and in varying weather conditions. We've also
included many other useful tips on driving.
4
-2 Defensive Driving
4
-3 Drunken Driving
4
-6 Control of a Vehicle
4
-6 Braking
4
-9 Steering
4
-11 Off-Road Recovery
4
-12 Passing
4
-13 Loss of Control
4
-14 Driving at Night
4
-16 Driving in Rain and on Wet Roads4
-19 City Driving
4
-20 Freeway Driving
4
-21 Before Leaving on a Long Trip
4
-22 Highway Hypnosis
4
-22 Hill and Mountain Roads
4
-24 Winter Driving
4
-27 Recreational Vehicle Towing
4
-28 Loading Your Vehicle
4
-30 Towing a Trailer
4
-38 Power Take-Off (PTO) Engine Speed Control
(If Equipped)

4-27
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, especially any
that 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.If you have a diesel engine, you may have to run it at a
higher speed to get enough heat. Then, shut the engine
off and close the window almost all the way to preserve
the heat. Start the engine again and repeat this only
when you feel really uncomfortable from the cold.
But do it as little as possible. Preserve the fuel as long
as you can. To help keep warm, you can get out of
the vehicle and do some fairly vigorous exercises every
half hour or so until help comes.
Recreational Vehicle Towing
Recreational vehicle towing means towing your vehicle
behind another vehicle
-- such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as ªdinghy towingº (towing your
vehicle with all four wheels on the ground) and ªdolly
towingº (towing your vehicle with two wheels on
the ground and two wheels up on a device known
as a ªdollyº).
Your vehicle was not designed to be towed with any of
its wheels on the ground. If your vehicle must be towed,
see ªTowing Your Vehicleº in the Index.

4-30
Towing a Trailer
CAUTION:
If you don't use the correct equipment and drive
properly, you can lose control when you pull a
trailer. For example, if the trailer is too heavy,
the brakes may not work well
-- or even at all.
You and your passengers could be seriously
injured. Pull a trailer only if you have followed
all the steps in this section. Ask your dealer for
advice and information about towing a trailer
with your vehicle.
NOTICE:
Pulling a trailer improperly can damage your
vehicle and result in costly repairs not covered
by your warranty.
NOTICE: (Continued)
NOTICE: (Continued)
To pull a trailer correctly, follow the advice in
this part, and see your dealer for important
information about towing a trailer with your
vehicle. Additional rear axle maintenance is
required for a vehicle used to tow a trailer.
See ªScheduled Maintenance Servicesº in
the Index.
To identify what the vehicle trailering capacity is for
your vehicle, you should read the information in
ªWeight of the Trailerº that appears later in this section.
Trailering is different than just driving your vehicle by
itself. Trailering means changes in handling, durability
and fuel economy. Successful, safe trailering takes
correct equipment, and it has to be used properly.
That's the reason for this part. In it are many
time
-tested, important trailering tips and safety rules.
Many of these are important for your safety and that
of your passengers. So please read this section carefully
before you pull a trailer.

4-31 If You Do Decide To Pull A Trailer
If you do, here are some important points:

There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
your rig will be legal, not only where you live but
also where you'll be driving. A good source for this
information can be state or provincial police.

Don't tow a trailer at all during the first 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.

Then, during the first 500 miles (800 km) that you
tow a trailer, don't drive over 50 mph (80 km/h) and
don't make starts at full throttle. This helps your
engine and other parts of your vehicle wear in at the
heavier loads.

If you have an automatic transmission, you can tow
in OVERDRIVE (
). You may want to shift the
transmission to THIRD (3) or, if necessary, a lower
gear selection if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).
If you have a manual transmission and you are
towing a trailer, it's better not to use the highest gear.Three important considerations have to do with weight:

the weight of the trailer,

the weight of the trailer tongue

and the weight on your vehicle's tires.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig.
For example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to
pull a trailer are all important. And, it can also depend
on any special equipment that you have on your vehicle.
Use the following chart to determine how much your
vehicle and trailer can weigh, based upon your vehicle
model and options.
3500HD models are incomplete vehicles and trailer
ratings are not assigned. Use the Gross Combination
Weight Rating (GCWR) chart to determine the
combination weight limit.