2019 GMC SIERRA DENALI trailer light connection

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
260 Driving and Operating Use caution while backing up when
towing a trailer, as the RCTA
detection zones that extend out
from the back of the vehicle do not
move further back when a trailer is
towed.
RCTA is disabled when the trailer
connection status is displayed.
RCTA can be turned off through
“ Collision/Detection Systems ” under
Vehicle Personalization 0 167 .
Turning the Features On or Off
Press
X on the center stack to
turn on or off the Front and Rear
Park Assist. The indicator light next
to the button comes on when the
features are on and turns off when
the features have been disabled. Front and Rear Park Assist can be
turned Off, On, or On with Towbar
through vehicle personalization. See
“ Park Assist ” under Vehicle
Personalization 0 167 . If Park Assist
is turned off through vehicle
personalization, the Park Assist
button will be disabled. To turn Park
Assist on again, select On in the
vehicle personalization menu. The
On with Towbar setting allows for
Park Assist to work properly with a
trailer hitch. Some larger trailer
hitches may not be compatible.
Turn off Park Assist when towing a
trailer.
To turn the RPA symbols on or off,
see “ Rear Camera Park Assist
Symbols ” under Vehicle
Personalization 0 167 .
Assistance Systems for
Driving If equipped, when driving the
vehicle in a forward gear, Forward
Collision Alert (FCA), Lane
Departure Warning (LDW), Lane
Keep Assist (LKA), Side Blind Zone Alert (SBZA), Lane Change Alert
(LCA), Forward Automatic Braking
(FAB), and/or the Front Pedestrian
Braking (FPB) System can help to
avoid a crash or reduce crash
damage.
Forward Collision Alert
(FCA) System If equipped, the FCA system may
help to avoid or reduce the harm
caused by front-end crashes. When
approaching a vehicle ahead too
quickly, FCA provides a red flashing
alert on the windshield and rapidly
beeps or pulses the driver seat.
FCA also lights an amber visual
alert if following another vehicle
much too closely.
FCA detects vehicles within a
distance of approximately 60 m
(197 ft) and operates at speeds
above 8 km/h (5 mph).

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
268 Driving and Operating How the System Works The LCA symbol lights up in the
side mirrors when the system
detects a moving vehicle in the next
lane over that is in the side blind
zone or rapidly approaching that
zone from behind. A lit LCA symbol
indicates it may be unsafe to
change lanes. Before making a lane
change, check the LCA display,
check mirrors, glance over your
shoulder, and use the turn signals.
Left Side Mirror
Display Right Side Mirror
Display
When the vehicle is started, both
outside mirror LCA displays will
briefly come on to indicate the
system is operating. When the
vehicle is in a forward gear, the left
or right side mirror display will light
up if a moving vehicle is detected in
the next lane over in that blind zone or rapidly approaching that zone.
If the turn signal is activated in the
same direction as a detected
vehicle, this display will flash as an
extra warning not to change lanes.
LCA is disabled when the trailer
connection status is displayed.
A DIC message may display. The
SBZA system still operates.
LCA can be disabled through
vehicle personalization. See Vehicle
Personalization 0 167 . If LCA is
disabled by the driver, the LCA
mirror displays will not light up.
When the System Does Not
Seem to Work Properly The LCA system requires some
driving for the system to calibrate to
maximum performance. This
calibration may occur more quickly if
the vehicle is driving on a straight
highway road with traffic and
roadside objects (e.g., guardrails,
barriers).
LCA displays may not come on
when passing a vehicle quickly, for
a stopped vehicle, or when towing a
trailer. The LCA detection zones that extend back from the side of
the vehicle do not move further back
when a trailer is towed. Use caution
while changing lanes when towing a
trailer. LCA may alert to objects
attached to the vehicle, such as a
trailer, bicycle, or object extending
out to either side of the vehicle.
Attached objects may also interfere
with the detection of vehicles. This
is normal system operation; the
vehicle does not need service.
LCA may not always alert the driver
to vehicles in the next lane over,
especially in wet conditions or when
driving on sharp curves. The system
does not need to be serviced. The
system may light up due to
guardrails, signs, trees, shrubs, and
other non-moving objects. This is
normal system operation; the
vehicle does not need service.
LCA may not operate when the LCA
sensors in the left or right corners of
the rear bumper are covered with
mud, dirt, snow, ice, or slush, or in
heavy rainstorms. For cleaning
instructions, see "Washing the
Vehicle" under Exterior Care 0 403 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 291Trailer 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
instrument panel to the right of the
steering column. See Instrument
Panel 0 6 . 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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
294 Driving and Operating 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.
If TSC is enabled, the Traction
Control System (TCS)/StabiliTrak/
ESC warning light will flash on the
instrument cluster. Reduce vehicle
speed by gradually removing your
foot from the accelerator. If trailer
sway continues, StabiliTrak/ESC
can reduce engine torque to help slow the vehicle. TSC will not
function if StabiliTrak/ESC is turned
off. See Traction Control/Electronic
Stability Control 0 243 .
{ WarningTrailer sway can result in a crash
and in serious injury or death,
even if the vehicle is equipped
with TSC.
If the trailer begins to sway,
reduce vehicle speed by
gradually removing your foot from
the accelerator. Then pull over to
check the trailer and vehicle to
help correct possible causes,
including an improperly or
overloaded trailer, unrestrained
cargo, improper trailer hitch
configuration, or improperly
inflated or incorrect vehicle or
trailer tires. See Towing
Equipment 0 285 for trailer ratings
and hitch setup
recommendations. Aftermarket Electronic Trailer
Sway Control Devices Some trailers may come equipped
with an electronic device designed
to reduce or control trailer sway.
Aftermarket equipment
manufacturers also offer similar
devices that connect to the wiring
between the trailer and the vehicle.
These devices may interfere with
the vehicle ’ s trailer brake or other
systems, including integrated
anti-sway systems, if equipped.
Messages related to trailer
connections or trailer brakes could
appear on the DIC. The effects of
these aftermarket devices may have
on vehicle handling or trailer brake
performance is not known.
{ Warning
Use of aftermarket electronic
trailer sway control devices could
result in reduced trailer brake
performance, loss of trailer
brakes, or other malfunctions, and
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
298 Driving and Operating on the tire sidewalls. Make sure to
re-adjust tire pressure to the
recommended level when the
process is complete.
Sensor Learning Steps
To complete the sensor-to-vehicle
learn process:
1. Touch Start on the Learn
Sensors screen. The horn
chirps twice and the Learning
Active screen appears on the
infotainment display.
2. Start with the driver side front
trailer tire.
3. Activate the tool near the valve
stem or adjust the air pressure
of this tire until the horn chirps
and all working vehicle and
trailer lights flash.
The process stops without
saving the sensor locations if
this step takes more than
two minutes.
4. Move to the next tire and
repeat Step 3 for each sensor.
The horn chirps twice when all
sensors are completed. 5. Return to the vehicle to
complete the setup.
Maintenance Reminders Select Yes to set up the
maintenance reminders for the
Trailer Profile. Follow the on-screen
prompts. The maximum number of
reminders is 10. Select No to skip
this step.
Status View The Status view shows:
.
Truck
.
Connection
.
Trailer
.
Maintenance Truck
1. Truck Status Page
2. Transmission Temperature
3. Average Fuel Economy with
Trailer Profile
Average Fuel Economy
Touch to view the average fuel
economy of the vehicle while the
Trailer Profile is active.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 299Transmission Temperature
Touch to view the temperature of
the transmission fluid graphic.
The graphic will indicate a
dangerous level if the temperature
is at 130 °C – 150 °C (270 °F – 300 °F).
Connections
1. Connections Status Page
2. Light Test Start Button
3. Trailer Electrical Diagnostics
Connections OK
If all of the trailer connections are
detected (Daytime Running Lights,
Left Turn Signal Light, Right Turn Signal Light, Reverse Lights, and
Electric Brakes, if equipped), the
view will display OK.
Connection Problem
If any of the trailer connections are
not detected, a message about the
connection issue will appear on the
Driver Information Center (DIC). The
infotainment display will also show
the connection issue in the
Connection Status view.
Diagnose View
Touch Diagnose to see more
information about the connection
problem.
This view will display 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. The Running Lights connection may
not detect partial outages. Activate
the light test to check all trailer
lamps. See “ Light Test ” following.
If the trailer is not equipped with
reverse lights or electric brakes and
you are receiving failure messages
in the DIC or on this view, turn off
the Reverse Lights Alert or the
Electric Brakes Alert setting in the
trailer ’ s profile page.
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
302 Driving and Operating The Custom Trailer Profiles and
Guest Trailer are in order of the
most frequently used.
All personalization features are
based on the settings for each
driver in vehicle personalization.
The list of Trailer Profiles is based
on vehicle personalization settings.
Guest Trailer
If the Guest Trailer Profile is the
active Trailer Profile, trailer
detection, connections status,
security, and the Tow/Haul reminder
alerts can be sent. The system will
not track total mileage or fuel
economy, but the system will track
trip mileage and fuel economy if the
Guest Trailer Profile is active. The
Trailer Tire Pressure Monitoring
System or maintenance reminders
cannot be set up for a Guest Trailer
Profile. The Guest Trailer Profile
cannot be edited.
Touch
p to learn more about the
Guest Trailer option. No Trailer Connected
When there is no trailer connected,
Trailer Profiles cannot be activated
but most options can be edited.
Trailer Brake Gain Memory
The system can memorize the brake
gain setting of a Trailer Profile or a
Guest Trailer Profile. When a Trailer
Profile or Guest Trailer Profile is
selected, and a brake gain setting is
set for that Trailer Profile, a quick
notice will appear to indicate that
the system has recalled that
profile ’ s brake gain setting.
If a Trailer Profile is already active
and the brake gain setting had been
set for that Trailer Profile, the quick
notice will trigger whenever the
ignition is turned on.
If there was an error in setting the
brake gain for a Trailer Profile, there
will be a notification. This pop-up
will not appear if the Guest Trailer
Profile is active or if there is no
trailer connected. Trailer brake gain should be set for
a specific trailering condition and
must be adjusted anytime vehicle
loading, trailer loading, or road
surface conditions change.
See “ Brake Gain ” for information
about the gain setting procedure.
Editing a Trailer Profile Trailer Profile View
Touch to edit any of the following
options in the Trailer Profile view:
.
Trailer Name
.
Hitch Type
.
Trailer Type
.
Tire Pressure Setup
.
Maintenance Reminders
.
Mileage
.
Average Fuel Economy
.
Reverse Lights Alert
.
Electric Brakes Alert
Touch Save to save the new value
to the Trailer Profile. Touching Back
will still save the previously entered
information.