2007 GMC YUKON 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 w/ Black Stripe: Battery Feed*
Dark Blue: Trailer Brake*
*The fuses for these two circuits are installed in
the underhood electrical center, but the circuits are
not connected. They should be installed by your
dealer 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 red/black stripe power feed
will not be connected to the battery until the
ring terminal is unstowed and connected to the
underhood electrical center. 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: Brake Signal to Trailer Connector
Red/Black: Battery
Light Blue/White: Brake Switch
White: Ground
It should be installed by your dealer 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 400.
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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 450for 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 400.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 you have an air conditioner and it is on,
turn it off.
2. Turn on your heater to full hot at the highest
fan speed and open the windows as
necessary.
3. In heavy traffic, let the engine idle in
NEUTRAL (N) while stopped. If it is safe to
do so, pull off the road, shift to PARK (P)
or NEUTRAL (N) 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.
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If there is still no sign of steam and your vehicle
is equipped with 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 you are parked.
If there is still no sign of steam and your vehicle is
equipped with an electric cooling fan, idle the
engine for ve minutes while you are 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 may 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
REDUCED ENGINE POWER 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 432.
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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 may
hear the fans spinning at low speed during
most everyday driving. The fans may turn off if no
cooling is required. Under heavy vehicle loading,
trailer towing, and/or high outside temperatures, or
if you are operating your air conditioning system,
the fans may change to high speed and you
may hear an increase in fan noise. This is normal
and indicates that the cooling system is
functioning properly. The fans will change to low
speed when additional cooling is no longer
required.
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(g)Inspect system. Check all fuel and vapor
lines and hoses for proper hook-up, routing, and
condition. Check that the purge valve works
properly, if equipped. Replace as needed.
(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 perform this service. See Engine
Coolant on page 445 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.
(k)If you drive regularly under dusty conditions,
inspect the lter at each engine oil change.
(l)Visually inspect belt for fraying, excessive
cracks, or obvious damage. Replace belt if
necessary.
(m)Check vent hose at transfer case for kinks
and proper installation.
Owner Checks and Services
These owner checks and services should be
performed at the intervals specied to help
ensure the safety, dependability, and emission
control performance of your vehicle. Your
GM Goodwrench
®dealer can assist you with
these checks and services.
Be sure any necessary repairs are completed at
once. Whenever any uids or lubricants are added
to your vehicle, make sure they are the proper
ones, as shown inRecommended Fluids and
Lubricants on page 561.
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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.
Courtesy Transportation
To enhance your ownership experience, we and
our participating dealers are proud to offer
Courtesy Transportation, a customer support
program for new vehicles.
For warranty repairs during the Bumper-to-Bumper
(U.S.) or Base Warranty Coverage period
(Canada), provided by the New Vehicle Limited
Warranty, interim transportation may be available
under the Courtesy Transportation program.
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 and is available only
at participating dealers. A separate booklet entitled
“Warranty and Owner Assistance Information”
furnished with each new vehicle provides detailed
warranty coverage information.
Scheduling Service Appointments
When your vehicle requires warranty service,
you should contact your dealer and request an
appointment. By scheduling a service appointment
and advising your service consultant of your
transportation needs, your dealer 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, let them know this,
and ask for instructions.
If the dealer 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.
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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.
Gather the important information you will
need from the other driver. Things like name,
address, phone number, driver’s license
number, vehicle license plate, vehicle make,
model and model year, Vehicle Identication
Number (VIN), insurance company and
policy number, and a general description of
the damage to the other vehicle.
If possible, call your insurance company from
the scene of the accident. They will walk you
through the information they will need. If
they ask for a police report, phone or go to
the police department headquarters the
next day and you can get a copy of the
report for a nominal fee. In some states
with “no fault” insurance laws, a report may
not be necessary. This is especially true
if there are no injuries and both vehicles are
driveable.
Choose a reputable collision repair facility for
your vehicle. Whether you select a GM
dealer or a private collision repair facility to
x the damage, make sure you are
comfortable with them. Remember, you will
have to feel comfortable with their work
for a long time.
Once you have an estimate, read it carefully
and make sure you understand what work
will be performed on your vehicle. If you have
a question, ask for an explanation. Reputable
shops welcome this opportunity.
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