2008 CHEVROLET AVALANCHE towing

Trailer Wiring Harness
Heavy-Duty Trailer Wiring Package
Your vehicle is equipped with the seven-wire trailer
towing harness. This harness with a seven-pin universal
heavy-duty trailer connector is attached to the rear
bumper beam. It is located next to the integrated trailer
hitch.The seven-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
Red: Battery Feed*
Dark Blue: Trailer Brake*
*The fuses for these two circuits are installed in the
underhood electrical center, but the wires are not
connected. They should be connected by your
dealer/retailer or a qualied service center.
If you are charging a remote (non-vehicle) battery, press
the Tow/Haul mode button located at the end of the
shift lever. This will boost the vehicle system voltage and
properly charge the battery. If the trailer is too light for
Tow/Haul mode, you can turn on the headlamps as
a second way to boost the vehicle system and charge
the battery.
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Electric Brake Control Wiring
Provisions
These wiring provisions are included with your vehicle
as part of the heavy-duty trailer wiring package.
These provisions are for an electric brake controller.
The instrument panel contains blunt cut wires near
the data link connector for the trailer brake controller.
The harness contains the following wires:
Dark Blue: Auxiliary
Red/Black: Battery
Light Blue: Brake Switch
White: Ground
The trailer brake controller should be installed by your
dealer/retailer or a qualied service center.
Trailer Recommendations
You must subtract your hitch loads from the Cargo
Weight Rating (CWR). CWR is the maximum weight
of the load your vehicle can carry. It doesn’t include the
weight of the people inside, but you can gure about
150 lbs. (68 kg) for each seat. The total cargo load
must not be more than your vehicles CWR.
Weigh your vehicle with your trailer attached, so that
you won’t go over the GVWR or GAWR. If you are using
a weight-distributing hitch, weigh the vehicle without
the spring bars in place.
You’ll get the best performance if you spread out the
weight of your load the right way, and if you choose the
correct hitch and trailer brakes.
For more information seeTowing a Trailer on page 4-47.
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If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn
you badly, even if you just open the hood. Stay
away from the engine if you see or hear steam
coming from it. Turn it off and get everyone
away from the vehicle until it cools down.
Wait until there is no sign of steam or coolant
before you open the hood.
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch re. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the
vehicle until the engine is cool.
SeeOverheated Engine Protection Operating
Mode on page 5-30for information on driving
to a safe place in an emergency.Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty. SeeOverheated Engine
Protection Operating Mode on page 5-30for
information on driving to a safe place in an
emergency.
If No Steam Is Coming From Your
Engine
The ENGINE OVERHEATED STOP ENGINE or the
ENGINE OVERHEATED IDLE ENGINE message, along
with a low coolant condition, can indicate a serious
problem.
If you get an engine overheat warning, but see or
hear no steam, the problem may not be too serious.
Sometimes the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. SeeTowing a Trailer on page 4-47.
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If you get the ENGINE OVERHEATED STOP ENGINE
or the ENGINE OVERHEATED IDLE ENGINE message
with no sign of steam, try this for a minute or so:
1. If the vehicle has an air conditioner and it is on,
turn it off.
2. Turn on the heater to the highest temperature and
at the highest fan speed and open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (NEUTRAL)
while stopped. If it is safe to do so, pull off the road,
shift to P (Park) or N (NEUTRAL) and let the
engine idle.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle immediately.
If there is still no sign of steam and your vehicle has an
engine-driven cooling fan, push down the accelerator
until the engine speed is about twice as fast as normal
idle speed for at least ve minutes while parked.
If there is still no sign of steam and your vehicle has an
electric cooling fan, idle the engine for ve minutes
while parked.If you still have the warning, turn off the engine and get
everyone out of the vehicle until it cools down. Also,
see “Overheated Engine Protection Operating Mode”
later in this section.
You might decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
ENGINE POWER IS REDUCED message is displayed,
an overheat protection mode which alternates ring
groups of cylinders helps prevent engine damage.
In this mode, you will notice a loss in power and engine
performance. This operating mode allows your vehicle
to be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in the
overheat protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair the
cause of coolant loss, change the oil and reset the oil
life system. SeeEngine Oil on page 5-15.
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4. With the coolant surge tank pressure cap off, start
the engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the
engine cooling fan.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge tank
until the level reaches the FULL COLD mark.5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
6. Verify coolant level after engine is shut off and the
coolant is cold. If necessary, repeat coolant ll
procedure steps 1 through 6.
Engine Fan Noise
Your vehicle has electric cooling fans. You might hear
the fans spinning at low speed during most everyday
driving. The fans can turn off if no cooling is required.
Under heavy vehicle loading, trailer towing, and/or
high outside temperatures, or if you are operating
the air conditioning system, the fans can change to
high speed and you might hear an increase in fan noise.
This is normal and indicates that the cooling system
is functioning properly. The fans change to low speed
when additional cooling is no longer required.
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(c)Visually inspect hoses and have them replaced if
they are cracked, swollen, or deteriorated. Inspect all
pipes, ttings, and clamps; replace with genuine parts as
needed. To help ensure proper operation, a pressure test
of the cooling system and pressure cap and cleaning the
outside of the radiator and air conditioning condenser is
recommended at least once a year.
(d)Inspect wiper blades for wear, cracking, or
contamination. Clean the windshield and wiper blades,
if contaminated. Replace wiper blades that are worn
or damaged. See Windshield Wiper Blade Replacement
on page 5-55andWindshield and Wiper Blades on
page 5-104for more information.
(e)Make sure the safety belt reminder light and safety
belt assemblies are working properly. Look for any other
loose or damaged safety belt system parts. If you see
anything that might keep a safety belt system from doing
its job, have it repaired. Have any torn or frayed safety
belts replaced. Also see Checking the Restraint Systems
on page 1-76.
(f)Lubricate all key lock cylinders, hood latch assembly,
secondary latch, pivots, spring anchor, release pawl,
midgate hinges, side storage box door hinges, tailgate
hinges, tailgate linkage, outer tailgate handle pivot
points, latch bolt, fuel door hinge, locks, and folding
seat hardware. More frequent lubrication may be
required when exposed to a corrosive environment.Applying silicone grease on weatherstrips with a clean
cloth will make them last longer, seal better, and
not stick or squeak.
(g)Check vent hose at transfer case for kinks and
proper installation.
(h)Change automatic transmission uid and lter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police, or delivery
service.
(i)Drain, ush, and rell cooling system. This service
can be complex; you should have your dealer/retailer
perform this service. See Engine Coolant on page 5-25
for what to use. Inspect hoses. Clean radiator,
condenser, pressure cap, and ller neck. Pressure test
the cooling system and pressure cap.
(j)A uid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the uid level checked. Add uid if needed.
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Towing and Road Service Exclusions
Specically excluded from Roadside Assistance
coverage are towing or services for vehicles operated
on a non-public roadway or highway, nes, impound
towing caused by a violation of local, Municipal, State,
Provincial, or Federal law, and mounting, dismounting
or changing of snow tires, chains, or other traction
devices.
Roadside Assistance is not part of or included in the
coverage provided by the New Vehicle Limited Warranty.
Chevrolet and General Motors of Canada Limited
reserve the right to make any changes or discontinue
the Roadside Assistance program at any time without
notication.
Scheduling Service Appointments
When your vehicle requires warranty service, contact
your dealer/retailer and request an appointment.
By scheduling a service appointment and advising your
service consultant of your transportation needs, your
dealer/retailer can help minimize your inconvenience.If your vehicle cannot be scheduled into the service
department immediately, keep driving it until it can be
scheduled for service, unless, of course, the problem is
safety-related. If it is, please call your dealership/retailer,
let them know this, and ask for instructions.
If the dealer/retailer requests that you simply drop the
vehicle off for service, you are urged to do so as early
in the work day as possible to allow for the same
day repair.
Courtesy Transportation
To enhance your ownership experience, we and our
participating dealers are proud to offer Courtesy
Transportation, a customer support program for vehicles
with the Bumper to Bumper (Base Warranty Coverage
period in Canada) and extended powertrain warranty
in both the U.S. and Canada.
Several courtesy transportation options are available to
assist in reducing your inconvenience when warranty
repairs are required.
Courtesy Transportation is not a part of the New Vehicle
Limited Warranty. A separate booklet entitled “Warranty
and Owner Assistance Information” furnished with each
new vehicle provides detailed warranty coverage
information.
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Repair Facility
We recommend that you choose a collision repair
facility that meets your needs before you ever need
collision repairs. Your dealer/retailer may have a
collision repair center with GM-trained technicians and
state of the art equipment, or be able to recommend
a collision repair center that has GM-trained technicians
and comparable equipment.
Insuring Your Vehicle
Protect your investment in your GM vehicle with
comprehensive and collision insurance coverage.
There are signicant differences in the quality of
coverage afforded by various insurance policy terms.
Many insurance policies provide reduced protection to
your GM vehicle by limiting compensation for damage
repairs by using aftermarket collision parts. Some
insurance companies will not specify aftermarket collision
parts. When purchasing insurance, we recommend that
you assure your vehicle will be repaired with GM original
equipment collision parts. If such insurance coverage
is not available from your current insurance carrier,
consider switching to another insurance carrier.
If your vehicle is leased, the leasing company may
require you to have insurance that assures repairs with
Genuine GM Original Equipment Manufacturer (OEM)
parts or Genuine Manufacturer replacement parts. Read
your lease carefully, as you may be charged at the
end of your lease for poor quality repairs.
If a Crash Occurs
Here is what to do if you are involved in a crash.
Check to make sure that you are all right. If you
are uninjured, make sure that no one else in
your vehicle, or the other vehicle, is injured.
If there has been an injury, call emergency services
for help. Do not leave the scene of a crash until
all matters have been taken care of. Move
your vehicle only if its position puts you in danger
or you are instructed to move it by a police officer.
Give only the necessary and requested information
to police and other parties involved in the crash.
Do not discuss your personal condition, mental
frame of mind, or anything unrelated to the crash.
This will help guard against post-crash legal action.
If you need roadside assistance, call GM Roadside
Assistance. SeeRoadside Assistance Program on
page 7-6for more information.
If your vehicle cannot be driven, know where the
towing service will be taking it. Get a card from
the tow truck operator or write down the driver’s
name, the service’s name, and the phone number.
Remove any valuables from your vehicle before it is
towed away. Make sure this includes your insurance
information and registration if you keep these
items in your vehicle.
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