2011 GMC YUKON XL wiring

Black plate (7,1)GMC Yukon/Yukon XL Owner Manual - 2011
Lighting 6-7
This button is located on the
overhead console.
When the wiring is connected to
an auxiliary roof‐mounted lamp,
pressing the bottom of the button
will activate the lamp and illuminate
an indicator light at the bottom of
this button. Pressing the top of the
button will turn off the roof‐mounted
lamp and indicator.The emergency roof lamp circuit
is fused at 30 amps, so the total
current draw of the attached lamps
should be less than this value.
The attachment points for the roof
lamp circuits are two blunt cut
wires located above the overhead
console, a dark green switched
power wire and a black ground wire.
For more information on roof mount
emergency lamp installation, please
visit the GM Upfitter website at
www.gmupfitter.com or contact your
dealer.
If the vehicle has this button,
the vehicle may have the snow
plow prep package. For further
information, see
Adding a Snow
Plow or Similar Equipment on
page 9‑94.
Interior Lighting
Instrument Panel
Illumination Control
D(Instrument Panel
Brightness): This feature controls
the brightness of the instrument
panel lights and is located next to
the exterior lamps control.
Push the knob to extend out and
then it can be turned.

Black plate (85,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-85
Safety Chains
Always attach chains between the
vehicle and the trailer. Cross the
safety chains under the tongue
of the trailer to help prevent the
tongue from contacting the road if it
becomes separated from the hitch.
Instructions about safety chains
may be provided by the hitch
manufacturer or by the trailer
manufacturer. If the trailer being
towed weighs up to 2 271 kg
(5,000 lbs) with a factory-installed
step bumper, safety chains may
be attached to the attaching points
on the bumper, otherwise, safety
chains should be attached to holes
on the trailer hitch platform. Always
leave just enough slack so the
combination can turn. Never allow
safety chains to drag on the ground.
Trailer Brakes
A loaded trailer that weighs more
than 900 kg (2,000 lbs) needs to
have its own brake system that is
adequate for the weight of the
trailer. Be sure to read and follow
the instructions for the trailer brakes
so they are installed, adjusted and
maintained properly.
Since the vehicle is equipped with
StabiliTrak
®, the trailer brakes
cannot tap into the vehicle's
hydraulic system.
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.

Black plate (86,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-86 Driving and Operating
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.
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.

Black plate (90,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-90 Driving and Operating
The Trailer Brake Display Page can
be displayed by performing any of
the following actions:
.Scrolling through the DIC
menu pages using the odometer
trip stem or the DIC Vehicle
Information button (if equipped).
.Pressing a Trailer Gain
button–If the Trailer Brake
Display Page is not currently
displayed, pressing a Trailer
Gain button will first recall the
current Trailer Gain setting.
After the Trailer Brake Display
Page is displayed, each press
and release of the gain buttons
will then cause the Trailer Gain
setting to change.
.Activating the Manual Trailer
Brake Apply lever
.Connecting a trailer equipped
with electric trailer brakes All DIC warning and service
messages must first be
acknowledged by the driver
by pressing the odometer trip
stem or the DIC Vehicle Information
button (if equipped) before the
Trailer Brake Display Page can be
displayed and Trailer Gain can be
adjusted.
TRAILER GAIN
–This setting is
displayed anytime the Trailer Brake
Display Page is active. This setting
can be adjusted from 0.0 to 10.0
with either a trailer connected or
disconnected. To adjust the Trailer
Gain, press one of the Trailer Gain
adjustment buttons located on the
Trailer Brake Control Panel. Press
and hold a gain button to cause the
Trailer Gain to continuously adjust.
To turn the output to the trailer off,
adjust the Trailer Gain setting to
0.0 (zero).
0.0 (zero) gain is the factory
default setting. To properly adjust
trailer gain, see the Trailer Gain
Adjustment Procedure later in this
section. TRAILER OUTPUT
–This is
displayed any time a trailer with
electric brakes is connected.
Output to the electric brakes is
based on the amount of vehicle
braking present and relative to
the Trailer Gain setting. Output is
displayed from 0 to 10 bars for each
gain setting.
The Trailer Output will
indicate “- - - - - -“ on the
Trailer Brake Display Page
whenever the following occur:
.No trailer is connected.
.A trailer without electric brakes
is connected (no DIC message
is displayed).
.A trailer with electric brakes
has become disconnected
(a CHECK TRAILER WIRING
message will also be displayed
on the DIC).

Black plate (91,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-91
.There is a fault present in the
wiring to the electric trailer
brakes (a CHECK TRAILER
WIRING message will also be
displayed on the DIC).
.There is a fault in the ITBC
system (a SERVICE TRAILER
BRAKE SYSTEM message will
also be displayed in the DIC).
Manual Trailer Brake Apply
The Manual Trailer Brake Apply
Lever is located on the Trailer
Brake Control Panel and is used to
apply the trailer ’s electric brakes
independent of the vehicle’s brakes.
This lever is used in the Trailer Gain
Adjustment Procedure to properly
adjust the power output to the trailer
brakes. Sliding the lever to the left
will apply only the trailer brakes.
The power output to the trailer is
indicated in the Trailer Brake
Display Page in the DIC. If the
vehicle’s service brakes are applied while using the Manual Trailer Brake
Apply Lever, the trailer output power
will be the greater of the two.
The trailer and the vehicle's brake
lamps will come on when either
vehicle braking or manual trailer
brakes are applied.
Trailer Gain Adjustment Procedure
Trailer Gain should be set for a
specific trailering condition and
must be adjusted any time vehicle
loading, trailer loading or road
surface conditions change.
Setting the Trailer Gain properly
is needed for the best trailer
stopping performance. A trailer
that is over-gained may result in
locked trailer brakes. A trailer that
is under-gained may result in not
enough trailer braking. Both of these
conditions may result in poorer
stopping and stability of the vehicle
and trailer.
Use the following procedure to
correctly adjust Trailer Gain for each
towing condition:
1. Make sure the trailer brakes are
in proper working condition.
2. Connect a properly loaded trailer to the vehicle and make
all necessary mechanical and
electrical connections. See
Vehicle Load Limits on
page 9‑23 for more information.
3. After the electrical connection is made to a trailer equipped with
electric brakes:
.A TRAILER CONNECTED
message will be briefly
displayed on the DIC
display.
.The Trailer Brake Display
Page will appear on the
DIC showing TRAILER
GAIN and TRAILER
OUTPUT.

Black plate (92,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-92 Driving and Operating
.In the Trailer Output display
on the DIC,“- - - - - -“will
disappear if there is no
error present. Connecting
a trailer without electric
brakes will not clear the
six dashed lines.
4. Adjust the Trailer Gain by using the gain adjustment (+ / -)
buttons on the Trailer Brake
Control Panel.
5. Drive the vehicle with the trailer attached on a level road
surface representative of the
towing condition and free of
traffic at about 32 to 40 km/h
(20 to 25 mph) and fully apply
the Manual Trailer Brake Apply
lever.
Adjusting trailer gain at speeds
lower than 32 to 40 km/h
(20 to 25 mph) may result in an
incorrect gain setting. 6. Adjust the Trailer Gain to just
below the point of trailer wheel
lock-up, indicated by trailer
wheel squeal or tire smoke when
a trailer wheel locks.
Trailer wheel lock-up may not
occur if towing a heavily loaded
trailer. In this case, adjust the
Trailer Gain to the highest
allowable setting for the towing
condition.
7. Re-adjust Trailer Gain any time vehicle loading, trailer loading or
road surface conditions change
or if trailer wheel lock-up is
noticed at any time while towing
Other ITBC Related DIC Messages
In addition to displaying TRAILER
GAIN and TRAILER OUTPUT
through the DIC, trailer connection
and ITBC system status is displayed
in the DIC. TRAILER CONNECTED
–This
message will be briefly displayed
when a trailer with electric brakes is
first connected to the vehicle. This
message will automatically turn off
in about ten seconds. The driver
can also acknowledge this message
before it automatically turns off.
CHECK TRAILER WIRING –This
message will be displayed if:
1. The ITBC system first determines connection to a
trailer with electric brakes and
then the trailer harness becomes
disconnected from the vehicle.
If the disconnect occurs while
the vehicle is stationary, this
message will automatically
turn off in about thirty seconds.
This message will also turn off if
the driver acknowledges this
message off or if the trailer
harness is re-connected.

Black plate (93,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-93
If the disconnect occurs while
the vehicle is moving, this
message will continue until
the ignition is turned off. This
message will also turn off if
the driver acknowledges this
message off or if the trailer
harness is re-connected.
2. There is an electrical fault in the wiring to the electric 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.

Black plate (97,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-97
This has the effect of reducing the
load on the front. However, the front
GAWR, rear GAWR, and the Gross
Vehicle Weight Rating (GVWR)
must never be exceeded.
{WARNING
On some vehicles that have
certain front mounted equipment,
such as a snow plow, it may be
possible to load the front axle to
the front gross axle weight rating
(GAWR) but not have enough
weight on the rear axle to have
proper braking performance. Ifthe brakes cannot work properly,
you could have a crash. To
help the brakes work properly
when a snow plow is installed,
always follow the snow plow
manufacturer or installer's
recommendation for rear ballast
to ensure a proper front and rear
weight distribution ratio, even
though the actual front weight
(Continued)
WARNING (Continued)
may be less than the front
GAWR, and the total vehicle
weight is less than the gross
vehicle weight rating (GVWR).
Maintaining a proper front and
rear weight distribution ratio is
necessary to provide proper
braking performance.
Total vehicle reserve capacity is
the difference between the GVWR
and the weight of the vehicle with
full fuel and passengers. It is the
amount of weight that can be added
to the vehicle before reaching
theGVWR. Keep in mind that
reserve capacity numbers are
intended as a guide when selecting
the amount of equipment or cargo
the vehicle can carry. If you are
unsure of the vehicle's front, rear,
or total weight, go to a weigh station
and weigh the vehicle. Your dealer
can also help you with this. The total vehicle reserve capacity
for the vehicle can be found
in the lower right corner of the
Certification/Tire label as shown
previously.
See your dealer for additional
advice and information about using
a snow plow on the vehicle. Also,
see
Vehicle Load Limits on
page 9‑23.
Emergency Roof Lamp
Provisions
Vehicles with the RPO VYU snow
plow prep package also have an
emergency roof lamp provision
package, RPO TRW. Wiring for the
emergency roof lamp is provided
above the overhead console. See
Auxiliary Roof-Mounted Lamp on
page 6‑6 for switch location.