warning lights CHEVROLET C/K 2003 Owners Manual

iv
Vehicle Damage Warnings
Also, in this book you will find these notices:
NOTICE:
These mean there is something that could damage
your vehicle.
In the notice area, we tell you about something that can
damage your vehicle. Many times, this damage would
not be covered by your warranty, and it could be costly.
But the notice will tell you what to do to help avoid
the damage.
When you read other manuals, you might see
CAUTION and NOTICE warnings in different
colors or in different words.
You'll also see warning labels on your vehicle.
They use the same words, CAUTION or NOTICE.
Vehicle Symbols
Your vehicle may be equipped with components and
labels that use symbols instead of text. Symbols,
used on your vehicle, are shown along with the text
describing the operation or information relating to a
specific component, control, message, gage or indicator.
If you need help figuring out a specific name of a
component, gage or indicator reference the following
topics in the Index:

ªInstrument Panelº

ªComfort Controlsº

ªAudio Systemsº
Also see ªWarning Lights and Gagesº in the Index.

2-
2-1
Section 2 Features and Controls
Here you can learn about the many standard and optional features on your vehicle, and information on starting,
shifting and braking. Also explained are the instrument panel and the warning systems that tell you if everything is
working properly
-- and what to do if you have a problem.
2
-2 Windows
2-5 Keys
2-7 Door Locks
2-8 Keyless Entry System (If Equipped)
2-12 Switchbanks
2-13 Theft
2-14 New Vehicle ªBreak-Inº
2-15 Ignition Positions
2-16 Starting Your Gasoline Engine
2-19 Starting the Diesel Engine
2-24 Starting Your DURAMAX
Diesel Engine
2-27 Engine Checks Before Operating
2-28 Engine Coolant Heater (If Equipped)
2-30 Diesel Engine Exhaust Brake (If Equipped)
2-31 Two-Speed Rear Axle Electric Shift Control
(If Equipped)
2
-34 Automatic Transmission Operation
2-36 Manual Transmission Operation
2-40 Parking
2-45 Parking Over Things That Burn
2-45 Engine Exhaust2
-46 Running Your Engine While You're Parked
(Automatic Transmission)
2
-47 Horn
2-48 Tilt Wheel (If Equipped)
2-48 Turn Signal/Multifunction Lever
2-55 Inter-Axle Differential Lock Control
(If Equipped)
2
-56 Rear Axle Differential Lock Control
(If Equipped)
2
-57 Exterior Lamps
2-60 Interior Lamps
2-61 Mirrors
2-63 Storage Compartments
2-65 Accessory Power Outlets
2-66 Trailer Connections (C4/C5 Models Only)
(If Equipped)
2
-67 Trailer Connections (C6/C7/C8 Models Only)
(If Equipped)
2
-68 The Instrument Panel-Your
Information System
2
-70 Instrument Panel Cluster
2-73 Warning Lights, Gages and Indicators

2-27
Engine Checks Before Operating
When you've started your engine, let it run for 20 to
30 seconds before you put a load on the engine. But
don't leave the vehicle while the engine is running.
Avoid unnecessary idling of diesel engine equipped
vehicles.
If the engine idles too long, the temperature of the
engine coolant will fall below the normal operating
range. Low engine operating temperature causes several
conditions which affect engine operation and reduce
engine life.
The engine should be permitted to go through a
warm
-up period. Operate the vehicle at a minimum of
600 rpm during the warm
-up period. During this period
and during operation, the following observations should
be made.
During this warm
-up period, check your warning lights
and gages:

If oil pressure doesn't begin to rise within
15 seconds of starting, stop the engine and
find the cause.
If the engine coolant temperature gage needle goes
into the hot area on the gage, stop the engine and
find the cause of the overheating.

If you have air brakes, the dual
-needle air pressure
gage should read at least 115 psi (790 kPa) for both
service systems before you try to move the vehicle.
When air pressure is below 60 psi (420 kPa), the
LOW AIR light will come on and you will hear a
tone alarm. If the pressure doesn't build up or
drops during warm
-up, stop the engine and find
the cause before you try to move the vehicle.
Recommended air pressure before actually driving
away is 120 psi (830 kPa).

The charging system light should come on when
the ignition key is turned to RUN or START and
should go out when the engine is running above idle.
If the light doesn't go out or comes back on during
normal engine operation, have the charging system
checked right away. (This light tells you if the
generator is not charging; it doesn't reflect the
condition of the battery.)

2-69
The main components of your instrument panel are the following:
A. Vents
B. Instrument Panel Cluster
C. Column Shift Lever (If Equipped)
D. Air Brake Control(s) (If Equipped)
E. Auxiliary Gages (If Equipped)
F. Exterior Lamp Control
G. Turn Signal Multifunction Lever
H. Hazard Warning Flashers ButtonI. Auxiliary Switches (If Equipped)
J. Audio System or Storage Area
K. Auxiliary Warning Lights
L. Comfort Controls
M. Instrument Panel Switchbank
N. Air Bag Off Switch (If Equipped)
P. Accessory Power Outlets

2-73 Tachometer
7.2L Caterpillar
Diesel Engine and
7.8L DURAMAX
Diesel EnginesGasoline and
6.6L DURAMAX
Diesel Engines
This gage shows the engine speed in revolutions per
minute (rpm).
Warning Lights, Gages and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause an
expensive repair or replacement. Paying attention to
your warning lights and gages could also save you or
others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle's functions. As you
will see in the details on the next few pages, some
warning lights come on briefly when you start the
engine just to let you know they're working. If you are
familiar with this section, you should not be alarmed
when this happens.

2-74
Gages can indicate when there may be or is a problem
with one of your vehicle's functions. Often gages and
warning lights work together to let you know when
there's a problem with your vehicle.
When one of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual's advice.
Waiting to do repairs can be costly
-- and even
dangerous. So please get to know your warning lights
and gages. They're a big help.
Safety Belt Reminder Light
When the key is turned to RUN or START, a light will
come on for several seconds to remind people to fasten
their safety belts.
The safety belt light will
also come on and stay on
for several seconds.
Safety Belt Reminder Tone (Option)
When the key is turned to RUN or START, a tone will
sound for several seconds to remind people to fasten
their safety belts.

2-78 Charging System Indicator Light
The charging system
indicator light may be
located in the instrument
panel cluster, or with the
auxiliary warning lights
in the center of the
instrument panel.
It should come on briefly when you turn on the ignition,
before the engine is running, as a check to show that it
is working.
If it stays on, or comes on while you are driving, have it
checked right away. You could have a loose generator
drive belt or some other problem.
Driving while this light is on will drain your battery. If
you must drive a short distance with the light on, turn
off your radio and other accessories.
Sustained driving with a generator failure could result in
a lack of back
-up braking if the engine quits or the
power steering pump should fail.
Voltmeter
When your engine is
running, the voltmeter
gage, at the right side of
the instrument panel cluster,
shows the charging
system voltage.
Readings in either warning zone indicate a possible
problem in the electrical system.
Readings in the low warning zone may occur when a
large number of electrical accessories are operating in the
vehicle and the engine is left at an idle for an extended
period. This condition is normal since the charging
system may not be able to provide full power at engine
idle. As engine speeds are increased, this condition
should correct itself because higher engine speeds allow
the charging system to create maximum power.
You can only drive a short time on the battery. Be sure
to shut off the radio, the fan or any unnecessary
accessories and have the system serviced.

2-79 Service Transmission Warning Light
(If Equipped)
If your vehicle has an Allison automatic transmission,
certain transmission malfunctions will turn this light on.
This light is located with
the auxiliary warning lights
in the center of the
instrument panel.
If this light comes on while you are driving, do not use
the transmission shift control. Using the transmission
shift control may result in the loss of forward gears. The
computer for the transmission senses a problem and
chooses a gear to stay in so that you can drive the
vehicle in that gear. You may not be able to drive as fast
or back up when this light is on.
NOTICE:
If the service transmission warning light comes
on while you are driving, it is a warning that
making a transmission ªrangeº change could
leave you stranded. The vehicle may not continue
to move if you change gears with the
transmission shift control. The transmission can't
operate in all gears because something is wrong.
Leave the shift control alone and drive directly to
a GM dealer for service. If you can't go in for
service immediately, have the vehicle towed.

2-80 Range Inhibited Warning Indicator
(If Equipped)
If your vehicle is equipped with an Allison
1000/2000/2400 series automatic transmission, a lighted
bar under the current gear selected will flash.
If your vehicle is equipped with an Allison MD
automatic transmission, the current gear selected on
the pushbutton display will flash.
The flashing bar or gear selection indicates that
transmission range shifts may not occur.
For detailed information on shift inhibit limitations, see
the Allison Automatic Transmission Operator's Manual
in your vehicle for further information.
Brake System Warning Light
Your vehicle has either hydraulic or air brakes.
Each system has different warning lights.
Hydraulic Brake System Warning Lights
Vehicles with hydraulic systems have two brake system
warning lights on the instrument panel.
If the BRAKE warning light
comes on, it means that the
fluid level in the master
cylinder reservoir is low or
there is another problem
with your hydraulic brakes.
When it comes on, you will also hear a warning tone.
The BRAKE warning light may come on, and the
warning tone may sound, when you're turning and
braking at the same time. This is normal. See ªHydraulic
Brake Systemsº in the Index.

2-81
If the amber SERVICE
BRAKES SOON warning
light comes on, it means
that there is something
wrong in the brake system.
When this light comes on, you will also hear a warning
tone. If this light comes on, have the system repaired
immediately.
Both of these lights should come on briefly every time
you start the engine. If they don't come on then, have
them fixed so they will be ready to warn you if there's a
problem. If one or both of these warning lights stay on
after you start the engine, there could be a brake
problem. Have your brake system inspected right away.If one or both of these lights come on and stay on while
you are driving, pull off the road and stop carefully. You
may notice that the pedal is harder to push. Or, the pedal
may go closer to the floor. It may take longer to stop. If
the BRAKE light is still on, have the vehicle towed for
service. See ªTowing Your Vehicleº in the Index. See
ªHydraulic Brake Systemsº in the Index for more
information.
CAUTION:
Your brake system may not be working properly
if a brake system warning light is on. Driving
with a brake system warning light on can lead to
an accident. If the light is still on after you've
pulled off the road and stopped carefully, have
the vehicle towed for service.