wiring GMC YUKON 2010 User Guide

2. There is an electrical fault in the wiring to theelectric trailer brakes. This message will continue
as long as there is an electrical fault in the trailer
wiring. This message will also turn off if the driver
acknowledges this message off.
To determine if the electrical fault is on the vehicle side
or trailer side of the trailer wiring harness connection,
do the following: 1. Disconnect the trailer wiring harness from the vehicle.
2. Turn the ignition OFF.
3. Wait ten seconds, then turn the ignition back to RUN.
4. If the CHECK TRAILER WIRING message re-appears, the electrical fault is on the
vehicle side.
If the CHECK TRAILER WIRING message only
re-appears when connecting the trailer wiring
harness to the vehicle, the electrical fault is on
the trailer side. SERVICE TRAILER BRAKE SYSTEM
–This message
will be displayed when there is a problem with the ITBC
system. If this message persists over multiple ignition
cycles there is problem with the ITBC system. Take the
vehicle to an authorized GM dealer to have the ITBC
system diagnosed and repaired.
If either the CHECK TRAILER WIRING or SERVICE
TRAILER BRAKE SYSTEM message is displayed while
driving the vehicle, power is no longer available to the
trailer brakes. When traffic conditions allow, carefully
pull the vehicle over to the side of the road and turn
the ignition off. Check the wiring connection to the
trailer and turn the ignition back on. If either of these
messages continues, either the vehicle or trailer needs
service.
An authorized GM dealer may be able to diagnose
and repair problems with the trailer. However, any
diagnosis and repair of the trailer is not covered under
the vehicle warranty. Please contact your trailer dealer
for assistance with trailer repairs and trailer warranty
information.
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Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
2. Start the engine
3. Shift into a gear
4. Release the parking brake
5. Let up on the brake pedal.
6. Drive slowly until the trailer is clear of the chocks.
7. Stop and have someone pick up and store thechocks.
Maintenance When Trailer Towing
The vehicle needs service more often when pulling a
trailer. See this manual's Maintenance Schedule or
Index for more information. Things that are especially
important in trailer operation are automatic transmission
fluid, engine oil, axle lubricant, belts, cooling system
and brake system. It is a good idea to inspect these
before and during the trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
The vehicle is equipped with the following wiring
harnesses for towing a trailer.
Basic Trailer Wiring
The trailer wiring harness, with a seven-pin connector,
is located at the rear of the vehicle and is tied to the
vehicle's frame. The harness connector can be plugged
into a seven-pin universal heavy-duty trailer connector
available through your dealer.
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
or a qualified service center.
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Heavy-Duty Trailer Wiring Harness Package
The vehicle is equipped with the seven-wire trailer
towing harness. This harness with a seven-pin universal
trailer connector is attached to a bracket on the hitch
platform.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
or a qualified service center.
If 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, 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 the vehicle as
part of the 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: Brake Signal to Trailer Connector
.Red/Black: Battery
.Light Blue/White: Brake Switch
.White: Ground
It should be installed by your dealer or a qualified
service center.
If the vehicle is equipped with an ITBC, the blunt cuts
exist, but are not connected further in the harness. If an
aftermarket trailer brake controller is installed, the ITBC
must be disconnected. Do not power both ITBC and
aftermarket controllers to control the trailer brakes at
the same time.
Trailer Recommendations
Subtract the hitch loads from the Cargo Weight Rating
(CWR). CWR is the maximum weight of the load the
vehicle can carry. It does not include the weight of the
people inside, but you can figure about 150 lbs. (68 kg)
for each passenger. The total cargo load must not be
more than the vehicles CWR.
Weigh the vehicle with the trailer attached, so the
GVWR or GAWR are not exceeded. If using a
weight-distributing hitch, weigh the vehicle without
the spring bars in place.
The best performance is obtained by correctly
spreading out the weight of the load and choosing
the correct hitch and trailer brakes.
For more information see Towing a Trailer
on
page 5‑49.
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Electrical System
Add-On Electrical Equipment
Notice:Do not add anything electrical to the vehicle
unless you check with your dealer first. Some
electrical equipment can damage the vehicle and
the damage would not be covered by the vehicle's
warranty. Some add-on electrical equipment can
keep other components from working as they
should.
Add-on equipment can drain the vehicle battery, even if
the vehicle is not operating.
The vehicle has an airbag system. Before attempting
to add anything electrical to the vehicle, see Servicing
Your Airbag-Equipped Vehicle
on page 2‑99and
Adding Equipment to Your Airbag-Equipped Vehicleon
page 2‑100.
Windshield Wiper Fuses
The windshield wiper motor is protected by an internal
circuit breaker and a fuse. If the motor overheats due
to heavy snow, etc., the wiper will stop until the motor
cools. If the overload is caused by some electrical
problem and not snow, etc., be sure to get it fixed.
Power Windows and Other Power
Options
Circuit breakers protect the power windows and other
power accessories. If the current load is too heavy, the
circuit breaker opens and then closes after a cool down
period, protecting the circuit until the problem is fixed or
goes away.
Fuses and Circuit Breakers
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
The wiring circuits in the vehicle are protected from
short circuits by a combination of fuses, circuit breakers
and fusible thermal links. This greatly reduces the
chance of fires caused by electrical problems.
Look at the silver-colored band inside the fuse. If the
band is broken or melted, replace the fuse. Be sure you
replace a bad fuse with a new one of the identical size
and rating.
If you ever have a problem on the road and don't
have a spare fuse, you can borrow one that has
the same amperage. Just pick some feature of your
vehicle that you can get along without –like the
radio or cigarette lighter –and use its fuse, if it is the
correct amperage. Replace it as soon as you can.
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