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4-65 Trailer Wiring Harness
Your vehicle is equipped with one of the following
wiring harnesses for towing a trailer or hauling a
slide
-in camper.
Basic Trailer Wiring Package
All regular and extended cab gasoline engine pickups
have a six
-wire trailer towing harness.
The six-wire harness is located at the rear of the vehicle
and is tied to the vehicle's frame. The harness requires
the installation of a trailer
-wiring harness connector,
which is available through your dealer.
The six
-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: Center High
-Mounted
Stoplamp (CHMSL)
If you need to upgrade your vehicle to heavy
-duty
trailering, a brake controller harness and an underbody
harness with a seven
-pin universal heavy-duty trailer
connector are available from your dealer.
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Basic Trailer Wiring Package (Diesel Engine)
Regular and extended cab pickups equipped with a
6.5L Turbo Diesel engine have an eight
-wire trailer
towing harness.
The trailer wiring harness with a seven-pin connector
and separate Center High
-Mounted Stoplamp (CHMSL)
connector are located at the rear of the vehicle and are
tied to the vehicle's frame.* The harness connector can
be plugged into a seven
-pin universal heavy-duty trailer
connector available through your GM dealer.* The single CHMSL wire is tied to the seven
-wire
harness and is used if your trailer or cap are equipped
with a CHMSL.
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
If you need to upgrade your vehicle to heavy
-duty
trailering, a brake controller harness and a seven
-pin
universal heavy
-duty trailer connector are available
from your GM dealer.
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Heavy-Duty Trailer Wiring Package (If Equipped)
Your pickup may be equipped with the 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, slide
-in camper or cap.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
A jumper harness for an electric trailer brake controller
and a trailer battery feed fuse are included with this
trailering package. (See ªInstrument Panel Jumper
Wiring Harnessº later in this section.)
If you need to tow a light
-duty trailer with a standard
four
-way round pin connector, an adapter connector is
available from your dealer.
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Camper/Fifth-Wheel Trailer Wiring Package
(If Equipped)
The eight
-wire camper harness is located under the front
edge of the pickup box on the driver's side of the vehicle,
attached to the frame bracket. A connector will have to be
added to the wiring harness which connects to the camper.
The eight
-wire harness contains the following
camper/trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back
-up Lamps
Light Blue: Center High
-Mounted
Stoplamp (CHMSL)
Red: Battery Feed
Dark Blue: Trailer Brake
A jumper harness for an electric trailer brake controller
and a trailer battery feed fuse are included with this
trailering package. (See ªInstrument Panel Jumper
Wiring Harnessº later in this section.)
If your vehicle is equipped with the ªHeavy-Duty
Traileringº option, please refer to ªHeavy
-Duty Trailer
Wiring Package,º earlier in this section.
When the camper
-wiring harness is ordered without the
heavy
-duty trailering package, an eight-wire harness
with a seven
-pin connector and separate CHMSL
connector are located at the rear of the vehicle and are
tied to the vehicle's frame.
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Instrument Panel Jumper Wiring Harness
This harness is included with the heavy-duty and
camper/fifth-wheel trailer wiring packages. The harness
is for an electric trailer brake controller and includes a
trailer battery feed fuse. This harness and fuse should be
installed by your dealer or a qualified service center.
Auxiliary Battery (If Equipped)
The auxiliary battery provision can be used to supply
electrical power to additional equipment that you may
choose to add, such as a slide
-in camper.
If your vehicle has this
provision, this relay
will be located on the
passenger's side of the
vehicle, next to the
auxiliary battery.
When using this provision, connection should only be
made to the upper stud (A) of the relay. Do not make
connections to the lower stud (B) of the relay.
The auxiliary battery circuit is protected by a Megafuse
located behind the auxiliary battery.
Be sure to follow the proper installation instructions that
are included with any electrical equipment that you install.
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NOTICE:
When using the auxiliary battery provision, the
electrical load must not exceed 30 amps. Always
turn off any electrical equipment when not in use.
Leaving electrical equipment on for extended
periods will drain your battery.
Power Winches
If you wish to use a power winch on your vehicle, only
use it when your vehicle is stationary or anchored.
NOTICE:
Using a power winch with the transmission in
gear may damage the transmission. When
operating a power winch, always leave the
transmission in NEUTRAL (N).
Use the regular brakes, set the parking brake, or block
the wheels to keep your vehicle from rolling.
Step-Bumper Pad
If your vehicle has a rear step bumper, it may
be equipped with a rear step pad at the center of
the bumper.
If you will be using the
bumper to tow a trailer, you
must remove the center
cutout circle to install
the trailer ball.
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2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren't touching
each other. If they are, it could cause a ground
connection you don't want. You wouldn't be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling, set
the parking brake firmly on both vehicles involved in
the jump start procedure. Put an automatic
transmission in PARK (P) or a manual transmission
in NEUTRAL (N). If you have a four
-wheel-drive
vehicle, be sure the transfer case is not in
NEUTRAL (N).
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets. Turn off all lamps
that aren't needed as well as radios. This will avoid
sparks and help save both batteries. In addition, it
could save your radio!
NOTICE:
If you leave your radio on, it could be badly
damaged. The repairs wouldn't be covered by
your warranty.
4. Open the hoods and locate the positive (+) and
negative (
-) terminal locations on the other vehicle.
Your vehicle has a remote positive (+) jump starting
terminal and a remote negative (
-) jump starting
terminal. The remote positive (+) terminal is located
behind a red plastic cover near the engine accessory
drive bracket. To uncover the remote positive (+)
terminal, open the red plastic cover.
On all V8 gasoline and diesel engines, the remote
negative (
-) terminal is located on the engine
accessory drive bracket. This is marked ªGNDºon
V8 gasoline engines. On V6 engines, the remote
negative (
-) terminal is located on a tab attached to
the engine accessory drive bracket where it is
marked ªGNDº.
You should always use the remote positive (+) and the
remote negative (
-) terminals instead of the positive (+)
and negative (
-) terminals on your battery.
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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 fan is spinning slower and 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 as the clutch more fully engages. So you may
hear an increase in fan noise. This is normal and should
not be mistaken as the transmission 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
partially disengages.
If a Tire Goes Flat
It's unusual for a tire to ªblow outº while you're driving,
especially if you maintain your tires properly. If air goes
out of a tire, it's much more likely to leak out slowly.
But if you should ever have a ªblowout,º here are a few
tips about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you'd use in a
skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop
-- well off the road if possible.
If a tire goes flat, the next part shows how to use your
jacking equipment to change a flat tire safely.
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your hazard
warning flashers.