GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-15555988) - 2022 - CRC - 12/3/21
142 Lighting
Turn and Lane-Change Signals
An arrow on the instrument cluster flashes
in the direction of the turn or lane change.
Move the turn signal lever all the way up or
down to signal a turn.
Raise or lower the lever for less than
one second until the arrow starts to flash to
signal a lane change. This causes the turn
signals to automatically flash three times.
It will flash six times if Tow/Haul Mode is
active. Holding the turn signal lever for
more than one second will cause the turn
signals to flash until the lever is released.
The lever returns to its starting position
whenever it is released.
If after signaling a turn or a lane change the
arrows flash rapidly or do not come on, a
signal bulb could be burned out.Replace any burned out bulbs. If a bulb is
not burned out, check the fuse. See
Fuses
and Circuit Breakers 0320.
Turn Signal On Chime
If the turn signal is left on for more than
1.2 km (0.75 mi), a chime sounds at each
flash of the turn signal. The message TURN
SIGNAL ON will also appear in the Driver
Information Center (DIC). To turn the chime
and message off, move the turn signal lever
to the off position.
Fog Lamps
If equipped with fog lamps, the button is on
the exterior lamp control, to the left of the
steering column. The ignition must be on for the fog lamps
to come on.
#:
Press to turn the fog lamps on or off.
A light will come on in the instrument
cluster.
When the fog lamps are turned on, the
parking lamps automatically turn on.
When the headlamps are changed to high
beam, the fog lamps also go off. When the
high-beam headlamps are turned off, the fog
lamps will come on again.
Some localities have laws that require the
headlamps to be on with the fog lamps.
GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-15555988) - 2022 - CRC - 12/3/21
Driving and Operating 279
Use only a round, seven-wire connector with
flat blade terminals meeting SAE J2863
specifications for proper electrical
connectivity.
The seven-wire harness contains the
following trailer circuits:
.Yellow/Grey: Left Stop/Turn Signal
.Green/Violet: Right Stop/Turn Signal
.Grey/Brown: Taillamps
.White: Ground
.White/Green: Back-up Lamps
.Red/Green: Battery Feed
.Dark Blue: Trailer Brake
To help charge a remote (non-vehicle)
battery change drive mode to Tow Haul.
If the trailer is too light for Tow/Haul Mode,
turn on the headlamps to help 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 harness should be installed by your
dealer or a qualified service center. Refer to the aftermarket electric trailer brake
controller owner's manual to determine wire
color coding of the electric trailer brake
controller. The wire colors on the brake
controller may be different from the vehicle.
Trailer Lamps
Always check 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 be
displayed if lighting circuit issues are
detected on the trailer.
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
0285.
Trailer Connection and Lamp Messages
When a trailer is properly connected and
working, no trailer connection or lamp
messages appear on the Driver Information Center (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 XXX LAMP appears when
there is a detected lamp or wiring fault
on the trailer. Check the trailer wiring and
lamps.
Turn Signals When Towing a Trailer
When properly connected, the trailer turn
signals should will illuminate to indicate the
vehicle is turning, changing lanes,
or stopping. When towing a trailer, the
arrows on the instrument cluster will
illuminate even if the trailer is not properly
connected or the bulbs are burned out.