tow CHEVROLET C/K 2003 User Guide

2-43
Vehicles built for use as tractors or towing vehicles have
two air brake controls. They look like this:To charge a trailer's air brake system do the following:
1. Move your tractor into the proper position.
2. Apply the parking brake by pulling the yellow
parking brake knob out.
3. Hook up the trailer air system properly.
4. Get into the tractor.
5. Push and hold down the regular brake pedal.
6. Push in both the yellow parking brake and the red
trailer air supply knobs. This will charge your
trailer's air system.
After a few minutes, the trailer system should be fully
charged. When it is, the air pressure gage will show
about 125 to 135 psi (862 to 931 kPa).
For driving with a trailer, the yellow and red
(if equipped) knobs must be pushed in. It's the same
when you're not pulling a trailer except that the red
trailer air supply knob must be pulled out.

2-44
CAUTION:
If you apply any one of the air brake parking
controls while the vehicle is moving, your rig will
stop suddenly. If you are not ready for this, you
or others could be injured. Don't apply any one
of these controls while you're driving, unless you
have to make an emergency stop.
If the air pressure drops below 60 to 70 psi (413 to
482 kPa), the primary brake light and warning buzzer
will come on. If the air pressure drops to 35 to 45 psi
(241 to 310 kPa), the red trailer air supply knob will
automatically pop out and apply the spring brakes on
the trailer.If the air pressure drops to 35 to 45 psi (241 to 310 kPa),
the yellow park brake knob will automatically pop out
and apply the spring brakes on the truck or tractor.
If you ever have a complete loss of air so that your air
brakes automatically apply, there is a way that the tow
operator can release the parking brakes to tow the
vehicle. See ªTowing Your Vehicleº in the Index.
CAUTION:
If your vehicle is left in gear, the engine can start
if the vehicle starts to roll. This can easily happen
if you have the diesel engine. Shift the
transmission into NEUTRAL (N) before you
leave the vehicle.

2-49 Turn and Lane-Change Signals
The turn signal has two upward (for right) and two
downward (for left) positions. These positions allow you
to signal a turn or a lane change.
To signal a turn, move the lever all the way up or down.
When the turn is finished, the lever will return
automatically.
An arrow on the instrument
panel cluster will flash in
the direction of the turn or
lane change.
To signal a lane change, just raise or lower the lever
until the arrow starts to flash. Hold it there until you
complete your lane change. The lever will return by
itself when you release it.As you signal a turn or a lane change, if the arrows don't
flash but just stay on, check the turn signal flasher and
circuit breaker. See ªFuses and Circuit Breakersº in
the Index.
If a bulb is burned out, replace it to help avoid an
accident. If the arrows don't go on at all when you
signal a turn, check the circuit breaker and for
burned
-out bulbs. (See ªFuses and Circuit Breakersº
in the Index.)
Headlamp High/Low-Beam Changer
To change the headlamps from low to high beam or high
to low beam, pull the multifunction lever all the way
toward you, then release it.
When the high beams are
on, this light on the
instrument panel cluster
will also be on.

2-50 Windshield Wipers
You control the windshield
wipers by turning the band
with the wiper symbol on it.
(Off): Turn the band on the lever to this symbol to
turn off the windshield wipers.
(Mist): For a single wiping cycle, turn the band to
this symbol. Hold it there until the wipers start, then let
go. The wipers will stop after one cycle. If you want
more cycles, hold the band on mist longer.
You can set the wiper speed for a long or short delay
between wipes. This can be very useful in light rain or
snow. Turn the band to one of the four delay settings to
choose the delay time. The further the band is turned
upward, the longer the delay will be. The further the
band is turned downward, the shorter the delay will be.
(Low Speed): For steady wiping at low speed,
turn the band toward you to the first solid band below
the delay settings.
(High Speed): For high-speed wiping, turn the
band further, to the second solid band below the delay
settings. To stop the wipers, move the band to off.
Be sure to clear ice and snow from the wiper blades
before using them. If they are frozen to the windshield,
carefully loosen or thaw them. If your blades do become
worn or damaged, get new blades or blade inserts. For
more information, see ªWindshield Wiper Blade
Replacementº in the Index.
Heavy snow or ice can overload your wipers. The
windshield wiper motor is protected from overload by a
circuit breaker and a fuse. If the motor overheats due to
heavy snow or ice the wiper will stop until the motor
cools. Although the circuit is protected from electrical
overload, overload due to heavy snow or ice may cause
wiper linkage damage. Always clear ice and heavy snow
from the windshield before using your windshield wipers.

2-58
The exterior lamp control has four positions:
OFF: Turning the control to this position turns off all
lamps except the Daytime Running Lamps (DRL).
(Parking Lamps): Turning the control to this
position turns on the parking lamps, together with the
following:

Marker Lamps

Taillamps

License Plate Lamps

Instrument Panel Lights
(Headlamps): Turning the control to this position
turns on the headlamps, together with the previously
listed lamps and lights.
You can switch your headlamps from low to high
beam by pulling the turn signal/multifunction lever
toward you. Pull the lever toward you again to return
to low beam.
A circuit breaker protects your headlamps. If you have
an electrical overload, your headlamps will flicker on
and off. Have your headlamp wiring checked right away
if this ever happens.
Headlamps On Reminder (If Equipped)
If you have this system, a tone will sound when your
headlamps and/or parking lamps are turned on and your
ignition is in LOCK or ACCESSORY.
Daytime Running Lamps
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the day.
DRL can be helpful in many different driving
conditions, but they can be especially helpful in the
short periods after dawn and before sunset. Fully
functional daytime running lamps are required on all
vehicles first sold in Canada.
The DRL system will make your headlamps come
on at reduced brightness when the following conditions
are met:

The ignition is on,

the exterior lamp control is off, and

the parking brake is released.
When the DRL are on, only your headlamps will be on.
The taillamps, sidemarker and other lamps won't be on.
Your instrument panel won't be lit up either.

2-61 Illuminated Entry
The delayed illumination feature will allow you to enter
or exit your vehicle with the lights on for about 20
seconds, after the door is closed or the ignition is cycled.
Reading Lamps (If Equipped)
If your vehicle has reading lamps, press the button next
to the lamp to turn the lamp on or off.
Mirrors
Inside Rearview Mirror (If Equipped)
Pull the tab under the mirror toward you to reduce glare
from headlamps behind you after dark. Push the tab
away from you to restore the mirror to the daytime
position.
Outside Rearview Mirrors
Adjust the outside rearview mirrors so you can see a
little of the side of your vehicle, and the area beside
your vehicle from a comfortable driving position. Some
mirrors can be folded in to enter narrow passageways.

2-66
Certain electrical accessories may not be compatible
with the accessory power outlet and could result in
blown vehicle or adapter fuses. If you experience a
problem, see your dealer for additional information on
accessory power outlets.
NOTICE:
Adding some electrical equipment to your vehicle
can damage it or keep other things from working
as they should. This wouldn't be covered by your
warranty. Check with your dealer before adding
electrical equipment, and never use anything that
exceeds the amperage rating.
When adding electrical equipment, be sure to follow the
proper installation instructions included with the equipment.
NOTICE:
Power outlets are designed for accessory plugs
only. Do not hang any type of accessory or
accessory bracket from the plug. Improper use of
the power outlet can cause damage not covered
by your warranty.
Trailer Connections (C4/C5 Models
Only) (If Equipped)
Heavy-Duty Trailer Wiring Package
Your vehicle may be equipped with an eight-wire trailer
towing harness. This harness, with a seven
-pin universal
heavy
-duty trailer connector, is attached to a bracket on
the platform hitch.
The Center High
-Mounted Stoplamp (CHMSL) wire is
tied next to the trailer wiring harness for use with a trailer.

2-67
The eight-wire harness contains the following
trailer circuits:

Yellow: Left Stop/Turn Signal

Dark Green: Right Stop/Turn Signal

Brown: Taillamps

White: Ground

Light Green: Back
-up Lamps

Light Blue: CHMSL

Red: Battery Feed

Dark Blue: Trailer Brake
Trailer Connections (C6/C7/C8
Models Only) (If Equipped)
If your vehicle has these trailer connections, they are
located at the rear of the cab for a tractor and at the rear
of the chassis when towing a trailer. There will be an air
connection and an electrical connection.
Be sure that the couplings to the trailer are
made correctly.
Air Connections
If you are not connecting the trailer air line connections
to another piece of equipment, be sure to replace their
protective caps.
Electrical Connections
This system is a seven-wire cable that will connect to
the trailer, supplying power to the trailer's lighting
system. When not in use, it is stored in the trailer
air
-hose storage bracket.
NOTICE:
Starting in 1998, the center pin (also known as
the auxiliary circuit) of the seven
-pin trailer
electrical connector will be wired to provide
continuous power for the trailer anti
-lock brake
systems when the ignition key is in the on
position. Care should be taken to insure that
continuous power on this circuit will not cause
damage to the trailer electrical system.
Consult with the trailer manufacturer for the
proper operation and checking procedures for
the trailer anti
-lock brake systems.

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.

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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.