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The GCWR can also be confirmed by
weighing the truck and trailer on a public
scale. The truck and trailer should be loaded
for the trip with passengers and cargo.
Gross Combined Weight (GCW) Alert
If equipped, the GCW Alert can display a
message in the Driver Information Center
(DIC), indicating that the estimated
combined weight of the vehicle and trailer
may exceed the vehicle’s GCWR, under
certain circumstances. See“Gross Combined
Weight Rating” above. The vehicle does not
actually measure the loaded weight of your
vehicle or trailer. It uses vehicle data to
estimate these weights after you begin
a trip. The alert will not activate unless:
.The feature is turned on in the trailering
application. See
Trailering App0296.
.The vehicle-trailer combination have been
used enough together for the software to
estimate the combined vehicle and trailer
weight.
.The estimated weight could exceed the
vehicle’s maximum GCWR.
If the GCW alert message is displayed, stop
the vehicle when it is safe and check the
vehicle and trailer weight using a scale. See
“Maximum Trailer Weight” below.
{Warning
Always determine the actual weights of
the loaded vehicle and trailer using a
vehicle scale before beginning a trip.
Never use the GCW Alert to determine
whether the vehicle and trailer are
properly loaded or overloaded. Do not
drive with an overloaded vehicle or
trailer. Death, serious injury, or property
damage could occur.
GCWR is only one of the maximum weight
ratings applicable to your vehicle and trailer.
The GCW Alert does not estimate whether the vehicle alone exceeds the GVWR, the
rear-axle weight exceeds GAWR-RR, the
trailer exceeds the Maximum Trailer Weight
Rating or the trailer tongue weight exceeds
the Maximum Tongue Weight Rating.
Always verify that the weight of the vehicle,
vehicle contents, trailer, trailer contents and
trailer tongue are below all of these
maximum weight ratings. See
“Maximum
Trailer Weight” below.
Gross Vehicle Weight Rating (GVWR)
For information about the vehicle's
maximum load capacity, see Vehicle Load
Limits 0210. When calculating the GVWR
with a trailer attached, the trailer tongue
weight must be included as part of the
weight the vehicle is carrying.
Maximum Trailer Weight
The maximum trailer weight rating is
calculated assuming the tow vehicle has a
driver, a front seat passenger, and all
required trailering equipment. This value
represents the heaviest trailer the vehicle
can tow, but it may be necessary to reduce
the trailer weight to stay within the GCWR,
GVWR, maximum trailer tongue load,
or GAWR-RR for the vehicle.
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Camper/Fifth-Wheel Trailer Wiring Package
For vehicles without the fifth-wheel/
gooseneck trailer package, the seven-wire
camper harness is under the rear bumper,
attached to the frame near the rear
crossmember. A connector must be added to
the wiring harness that connects to the
camper.
The harness contains the following
camper/trailer circuits:Stop/Turn
Signal Left Yellow/Blue
Stop/Turn Signal
Right Green/Violet
Tail/Parking Lamps Gray/Brown Reverse Lamps White/Green
Battery Feed Red/Green
Ground White
Electric Trailer Brake Blue
If equipped with the heavy-duty trailering
option, see “Heavy-Duty Trailer Wiring
Harness Package” earlier in this section.
When the camper-wiring harness is ordered
without the heavy-duty trailering package, a
seven-wire harness with a seven-pin
connector is at the rear of the vehicle and is
tied to the vehicle's frame.
Trailer Lamps
Always check that all trailer lamps are
working at the beginning of each trip, and
periodically on longer trips.
If equipped, the Trailering App will monitor
the RH turn/brake lamp circuit, LH turn/
brake lamp circuit, running lamp circuit, and
reverse lamp circuits on the trailer. DIC
messages and Trailering App alerts may
display if lighting circuit issues are detected
on the trailer. When a trailer cannot be detected, the
trailer-related DIC messages and/or
Trailering App alerts will not display.
Pressing START LIGHT TEST in the Trailering
App automatically activates trailer lamps.
The Trailering App is not a substitute for
manually inspecting your trailer lamps. See
Trailering App
0296.
Trailer Connection and Lamp Messages
When a trailer is properly connected and
working, no trailer connection or lamp
messages appear on the DIC. However; if
the vehicle detects an issue with a trailer
connection or lamp, you may see the
following DIC message(s):
.TRAILER DISCONNECTED CHECK
CONNECTION appears when a connected
trailer is disconnected. It appears
immediately when the vehicle is on,
or upon the next start-up if the trailer
was disconnected while the vehicle was
off. Check the trailer connection as
appropriate.
.CHECK TRAILER LAMP appears when there
is a detected lamp or wiring fault on the
trailer. Check the trailer wiring and lamps.
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Warning (Continued)
injury, death, or property damage. Only
use the ITBC system with electric or
electric over hydraulic trailer brake
systems.
Trailer Brake Control Panel
1. Manual Trailer Brake Apply Lever
2. Trailer Symbol
3. Trailer Gain Adjustment Buttons
The trailer symbol on the control panel will
light amber when a trailer with electric
brakes is connected.The ITBC control panel is on the center stack
or center console. See
Instrument Panel
Overview 05. The control panel allows
adjustment to the amount of output,
referred to as Trailer Gain, available to the
trailer brakes and allows manual application
of the trailer brakes. Use the ITBC control
panel and the DIC trailer brake display page
to adjust and display power output to the
trailer brakes.
Trailer Brake DIC Display Page
The ITBC display page indicates:
.Trailer Gain setting
.Output to the trailer brakes
.Trailer connection
.System operational status
To display:
.Scroll through the DIC menu pages
.Press a Trailer Gain (+) or (−) button
.Activate the Manual Trailer Brake Apply
Lever
TRAILER GAIN: Press a Trailer Gain button to
recall the current Trailer Gain setting. Each
press and release of the gain buttons will
then change the Trailer Gain setting. Press
the Trailer Gain (+) or (-) to adjust. Press and
hold to continuously adjust the Trailer Gain. To turn the output to the trailer off, adjust
the Trailer Gain setting to 0.0. This setting
can be adjusted from 0.0 to 10.0 with a
trailer connected or disconnected.
TRAILER OUTPUT: This displays anytime a
trailer with electric brakes is connected.
Output to the trailer brakes is based on the
amount of vehicle braking present and
relative to the Trailer Gain setting. Output is
displayed from 0 to 100% 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 displays.
.A trailer with electric brakes has become
disconnected. A CHECK TRAILER WIRING
message displays on the DIC.
.There is a fault present in the wiring to
the trailer brakes. A CHECK TRAILER
WIRING message displays on the DIC.
.The ITBC system is not working due to a
fault. A SERVICE TRAILER BRAKE SYSTEM
message displays in the DIC.
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Driving and Operating 293
Manual Trailer Brake Apply Lever
Slide this lever to apply the trailer’s electric
brakes independent of the vehicle’s brakes.
Use this lever to adjust the Trailer Gain to
achieve proper power output to the trailer
brakes. Under certain circumstances, this
lever can also be used to apply additional
trailer braking. The trailer and vehicle brake
lamps will come on when either the vehicle
brakes or trailer brakes are applied and
properly connected.
Trailer Gain Adjustment Procedure
Trailer Gain should be set for a specific
trailering condition and it must be
readjusted anytime vehicle loading, trailer
loading, or road surface conditions change.
{Warning
Trailer brakes that are over-gained or
under-gained may not stop the vehicle
and the trailer as intended and can result
in a crash. Always follow the instructions
to set the Trailer Gain for the proper
trailer stopping performance.To adjust Trailer Gain for each towing
condition:
1. Drive the vehicle with the trailer attached on a level road surface
representative of the towing condition
and free of traffic at about 32–40 km/h
(20–25 mph) and fully apply the Manual
Trailer Brake Apply Lever.
Adjusting Trailer Gain at speeds lower
than 32–40 km/h (20–25 mph) may
result in an incorrect gain setting.
2. Adjust the Trailer Gain, using the Trailer Gain (+) or (−) adjustment buttons, 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. Adjust
the Trailer Gain to the highest allowable
setting for the towing condition.
3. Readjust Trailer Gain anytime 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
TRAILER BRAKES CONNECTED: This message
will briefly display when a trailer with
electric brakes is first connected to the
vehicle. This message will automatically turn
off in about 10 seconds. This message can
be acknowledged before it automatically
turns off.
CHECK TRAILER WIRING: This message will
display if:
.The ITBC system first determines
connection to a trailer with electric brakes
and then the trailer harness becomes
disconnected from the vehicle.
.The disconnect occurs while the vehicle is
stationary, this message will
automatically turn off in about
30 seconds. This message will also turn
off if it is acknowledged or if the trailer
harness is reconnected.
.The disconnect occurs while the vehicle is
moving, this message will continue until
the vehicle is turned off. This message
will also turn off if it is acknowledged or
if the trailer harness is reconnected.
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.There is an electrical fault in the wiring to
the 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 it is acknowledged.
To determine whether the electrical fault is
on the vehicle side or trailer side of the
trailer wiring harness connection: 1. Disconnect the trailer wiring harness from the vehicle.
2. Turn the vehicle off.
3. Wait 10 seconds, then turn the vehicle back to RUN.
4. If the CHECK TRAILER WIRING message reappears, the electrical fault is on the
vehicle side.
5. If the CHECK TRAILER WIRING message only reappears when connecting the
trailer wiring harness to the vehicle, the
electrical fault is on the trailer side.
SERVICE TRAILER BRAKES or REDUCED
TRAILER BRAKING: This message will display
if the electric trailer brake performance is
either reduced or non-functional.
HOLD LAST KNOWN GAIN: This message will
display if it is no longer possible to adjust
the trailer brake gain. Trailer brakes may or
may not still be functional, and it is not possible to adjust brake gain based on road
conditions. The trailer brakes may remain
functional until the next time the vehicle is
turned off.
TRAILER BRAKES DISABLED SERVICE
REQUIRED: This message will display when
there is a problem with the ITBC system.
If this message continues over multiple
restarts, have the vehicle serviced.
If either the CHECK TRAILER WIRING, TRAILER
BRAKES DISABLED SERVICE REQUIRED,
SERVICE TRAILER BRAKES, or REDUCED
TRAILER BRAKING message displays while
driving, the ITBC system may not be fully
functional or may not function at all. When
traffic conditions allow, carefully pull the
vehicle over to the side of the road and turn
the vehicle off. Check the wiring connection
to the trailer and turn the vehicle back on.
If either of these messages continue, either
the vehicle or trailer needs service.
{Warning
Driving while the trailer braking system is
malfunctioning may increase loading on
the vehicle's braking system or lead to
(Continued)
Warning (Continued)
trailer instability. Use caution. Drive
slowly and allow for increased stopping
distances.
A 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. Contact
your trailer dealer for assistance with trailer
repairs and trailer warranty information.
Trailer Sway Control (TSC)
Vehicles with StabiliTrak/Electronic Stability
Control (ESC) have a Trailer Sway Control
(TSC) feature. Trailer sway is unintended
side-to-side motion of a trailer while towing.
If the vehicle is towing a trailer and the TSC
detects that sway is increasing, the vehicle
brakes are selectively applied at each wheel,
to help reduce excessive trailer sway.
If equipped with the Integrated Trailer Brake
Control (ITBC) system, and the trailer has an
electric brake system, StabiliTrak/ESC may
also apply the trailer brakes.
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If trailer dimensions are out of range, this
feature will be unavailable.
Status View
If a trailer is connected, the Status view
shows status information for the active
trailer profile.
If no trailer is connected, the Status view
shows the last trailer profile with a status of
Not Connected.
The Status view shows:
.Lights
.Tires
.Maintenance
.Cameras
.Checklists
.Weight
.Towing AssistScroll right or left to see more options.
Each section shows high level status
information for the feature. Selecting a
section will open up a new screen with
additional information and/or options.
Selecting a camera view will open up a new
screen to preview the camera image. The
status view displays mileage and fuel
economy information.
Lights
This view displays the names of the trailer
connector pins, a graphic of the trailer
connector, and a graphic of the back of the
trailer.
Any connector pin that failed will be amber
color, and the location of the corresponding
connection will be highlighted on the
graphic of the back of the trailer.
If a trailer connection is detected without
any faults, the view will display No Issues
Found.
When a trailer is connected, the Trailering
App detects the trailer connection using the
Stop/Turn Signal lighting circuits and alerts
the driver by requesting a trailer profile
setup through the Trailering App on the
infotainment screen. If a default trailer
profile is selected, the Trailering App will not
display a Trailer Detection Alert to the user
when a trailer is connected.
When a trailer is connected and the vehicle
is off, the Trailering App will periodically
pulse the lighting circuits of the trailer to
verify it is still connected. The trailer lights
may periodically flash as a result of this
trailer connection detection. These flashes
may be more visible in dark ambient light
environments. The flashing or flickering
lights are a normal condition and the
Trailering App has built-in protections to
prevent the battery from draining. When
Theft Alert is enabled, the frequency and
pattern of this flashing will change.
If a connected trailer becomes disconnected,
a message about the trailer disconnect will
appear on the Driver Information Center
(DIC) immediately (if vehicle is on) or the
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next time the vehicle is turned on (if trailer
was disconnected while vehicle is off). Check
your trailer connection if needed.
Connection Problem
If any of the trailer connections are lost, a
message about the connection issue appears
on the DIC. The infotainment screen will also
show the connection issue in the Lights
Status view.
Connection Trailer Lighting Faults Detected
The Trailering App monitors for electrical
faults on the trailer lights. A message about
the lighting issue appears on the DIC. The
infotainment screen will also show the
lighting issue in the Lights Status view.
Repair your trailer lights if needed. A trailer
lighting issue is not covered by your GM
warranty.
The Running Lights connection may not
detect partial outages. Activate the light test
to check all trailer lamps. See“Light Test”
following. Light Test
Touch Start Light Test to cycle the trailer
lights on and off to determine if they are
working. The test follows this sequence:
1. The running lights turn on first and remain on throughout the sequence.
2. The brake lights turn on for about two seconds.
3. The left turn signal light flashes three times.
4. The right turn signal light flashes three times.
5. The reverse lights turn on for about two seconds.
6. Steps 2-5 repeat for approximately one minute and 45 seconds, or until the
test deactivates.
Touch Stop to stop the test. The test will
automatically end after one minute and
45 seconds.
The sequence also deactivates when any of
the following occur:
.The vehicle is turned off.
.The transmission is shifted out of
P (Park).
.The brake pedal is pressed.
.The turn signal is activated.
.The hazard warning lights are activated.
Tires
Tire Pressure and Temperature
If the TTPMS sensor-to-vehicle learn process
was completed, the status view will display
the current tire pressure and temperature of
the trailer tires related to the active Trailer
Profile. If a tire’s pressure is low or high, the
color of the pressure value will be amber.
If a sensor malfunctions, the values are
dashed lines. If the screen displays “Service
Tire Pressure Monitoring System,” the
vehicle needs to be taken to a dealer for
service.
Touch to set up the TTPMS for the Trailer
Profile. See “Trailer Tire Pressure Setup”
previously in this section for details on the
setup. Also, touch Sensor Setup if the trailer
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tires were rotated or if the tire pressure
sensors in the tires were replaced for this
Trailer Profile. The vehicle will need to
relearn the tire sensors and their locations.
See“Trailer Tire Pressure Setup” previously
in this section.
Touch Edit Target Pressure to change the
recommended tire pressure for the trailer
tires. This will change the number at which
the vehicle displays alerts related to trailer
tire pressure.
Maintenance
Touch to view a list of maintenance
reminders for the Trailer Profile.
The Maintenance Status view displays
reminders for the Trailer Profile. Touch a
reminder to view, reset, delete, or edit it. Resetting a reminder will reset the time and
mileage values for the reminder. The
progress bar turns yellow when the
maintenance item reaches 90% complete.
The progress bar turns red when the
maintenance item reaches 100% complete.
Touch New Reminder to add a new
maintenance reminder.
Suggested reminders that were previously
set will not appear. Suggested reminders
that have not been set have empty boxes
next to them. The maximum number of
reminders is 50.
Maintenance Notifications
Touch Reset to reset time and mileage
values for the reminder.
Touch Remind Me Later to delay the
reminder.
If an Upcoming Alert (90%) is dismissed, it
will not appear again.
If a Maintenance Due Alert (100%) is
dismissed, it will appear when the vehicle is
turned off and back on again.
Always follow all of the maintenance
instructions that came with your trailer.
Cameras
This view shows a preview of the selected
camera view. Touch X to exit the preview.
Touch the camera icon to open the
camera app.
Checklist View
This view shows the recommended steps to
take before towing a trailer.