2004 CHEVROLET KODIAK trailer

Trailer Brake Hand Control Valve
If your vehicle has this feature, the control is mounted
on the floor console.
This feature lets you apply
the trailer brakes without
applying the tractor brakes.
You can apply the trailer brakes a little or apply them all
the way if you have to. Use this control only when
you are driving. Do not use it for parking or to hold the
rig on a hill.{CAUTION:
Using the trailer brake hand control for parking
or for holding the vehicle on a hill may not
keep the vehicle from rolling. This can happen
if someone hits the valve by accident, or if air
pressure bleeds from the system. If the vehicle
rolls, you or others could be injured. To park
the vehicle or hold it on a hill, use the parking
brake properly.
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Trailer Connections
(C4/C5 Models Only)
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.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
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Trailer Connections
(C7/C8 Models Only)
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.
Power Take-Off (PTO)
If your vehicle is equipped
for the addition of a PTO,
this factory installed
switch will be located in
the instrument panel
switchbank.
Before using a PTO, refer to the manufacturer’s or
installer’s instructions.
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5. Then replace the
pressure cap. Be sure
the pressure cap is
hand-tight and
fully seated.
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the clutch is not fully engaged. This improves
fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or high outside
temperatures, the fan speed increases when the clutch
engages. So you may hear an increase in fan noise.
This is normal and should not be mistaken as thetransmission slipping or making extra shifts. It is merely
the cooling system functioning properly. The fan will
slow down when additional cooling is not required and
the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
Power Steering Fluid
See your Maintenance Schedule for when to check your
power steering fluid.
How To Check Power Steering Fluid
Check your power steering fluid only when the engine is
warm. If the engine isn’t warm, you probably won’t
get an accurate reading.
If the fluid level is between the MIN and MAX marks,
you have enough. If you need fluid, add only enough of
the proper fluid to bring it in between the MIN and
MAX marks.
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Vehicle Identication
Vehicle Identication Number (VIN)
This is the legal identifier for your vehicle. It appears on
a plate in the front corner of the instrument panel, on
the driver’s side. You can see it if you look through the
windshield from outside your vehicle. The VIN also
appears on the Vehicle Certification and Service Parts
labels and the certificates of title and registration.
Engine Identication
The 8th character in your VIN is the engine code. This
code will help you identify your engine, specifications
and replacement parts.
Service Statement
One of these statements is on your GVW Rating label.
Here is what each one means.
TRUCK SERVICE:A vehicle made to carry property or
special equipment. It is made for uniform frame
loading. That includes using the vehicle to pull a full
trailer.
TRUCK-TRACTOR:A vehicle made to draw other
vehicles. It is made to carry part of the load of the trailer.
It is made for point frame loading, usually for a
semi-trailer (fifth-wheel).
MAX. VERT. CG:The highest allowable vertical center
of gravity, at the highest allowable GVWR. It is
measured from the level ground in inches.
TRUCK-CANADA:A vehicle first sold in Canada with a
non-school bus application, or cab models with regular
production option RQ2 (truck service).
TRACTOR-CANADA:A cab model first sold in Canada
with regular production option RQ3 (truck-tractor
service).
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Fuse Usage
RH PARK LP Right-hand Parking Lamps
LH PARK LP Left-hand Parking Lamps
RADIO U Radio
PWR WINDOW Power Windows
BRAKE ISO Brake Warning Lamp
SPARE Spare Fuse
L-RR TRUCK Left Rear Trailer Wiring
SPARE Spare Fuse
SPARE Spare Fuse
SPARE Spare Fuse
R-RR TRUCK Right Rear Trailer Wiring
SPARE Spare Fuse
Relay Usage
BRAKE LAMPC4/C5 Brake Lamps,
C6/C7/C8 Tractor/Trailer Wiring
IGN 4 IgnitionRelay Usage
MARKER LP Sidemarker and Clearance Lamps
HTD FUEL LB7/LG4 Heated Fuel
AIR HTR LG4 Air Heater
ECU MAINTAIN LG4 Electronic Control Unit
DRL Daytime Running Lamps
CHMSL ISO Center High Mounted Stop Lamp
HTD MIRR Heated Mirrors
R-TRN TLR Right Trailer Turn Signal
L-TRN TLR Left Trailer Turn Signal
SPARE Spare Relay
SPARE Spare Relay
SPARE Spare Relay
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Circuit Breaker Usage
1 Stoplamps
2 Center High Mounted Stop Lamps
3 Parking Lamps
4 Powertrain Control Module
5 Auxiliary Wiring
6 Heater/Air Conditioning
7 Hazard Warning FlashersCircuit Breaker Usage
8 Power Post
9 Courtesy Lamps
10Warning Lights, Gages and
Indicators
11 Crank
12 Rear Axle
13Trailer Turn Signals/Hazard Warning
Flashers
14 Radio/Chime
15 Daytime Running Lamps
16 Air Bag System
17 Exterior/Interior Lamps
18 Parking Brake
19 Accessory Power
20 Ignition
21 Sidemarker Lamps
22 Turn Signal/Backup Lamps
23 Transmission
24 Chassis
A Spare
B Spare Fuse Block 2
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Scheduled Maintenance
The services shown in this schedule up to 100,000 miles
(166 000 km) should be repeated after 100,000 miles
(166 000 km) at the same intervals for the life of
this vehicle. The services shown after 100,000 miles
(166 000 km) should be repeated at the same miles (km)
after those intervals for the life of this vehicle.
Gasoline engine vehicles have a computer that lets you
know when to change your engine oil. This is not
based on mileage, but on engine revolutions and engine
operating temperature. When the computer has
calculated that the oil needs changing, the GM Oil Life
System will indicate that a change is necessary.
The “Footnotes” at the end of this Maintenance
Schedule further explain maintenance services.
SeeService Publications Ordering Information on
page 7-7.
100 Miles (160 km)
❑Wheel stud nut service.(46)
1,000 Miles (1 600 km)
❑Wheel stud nut service.(46)
❑Rear axle air shift motor service.(11)
7,500 Miles (12 000 km)
❑Gasoline Engine Only: Check Oil Life System. If
engine oil and filter are changed, reset system. See
“Engine Oil (Gasoline Engine)” in the Index.(3) (9)
❑Check fluid levels (or every 3 months, whichever
occurs first).(1) (6)
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(12)
❑Wheels and tires service.(15)
❑Hydraulic brake service (or every 6 months, whichever
occurs first).(7) (46)
❑Parking brake service (or every 6 months, whichever
occurs first).(8)
❑Air brake service (or every 6 months, whichever
occurs first).(39)
❑Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first).(40)
❑Check air brake relay valve operation and check for
leaks (or every month, or every 300 hours, whichever
occurs first).
❑Clean air brake application valve (or every 3 months,
or every 300 hours, whichever occurs first). Lubricate
linkage.
❑Air brake chamber service (or every 2 months,
whichever occurs first).(41)
❑Trailer brake hand control valve service (or every
3 months, or every 900 hours, whichever occurs
first).(42)
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