GMC 2016 Yukon XL Denali Owner's Manual page 228

Selecting the Follow Distance Gap
When a slower moving vehicle is
detected ahead within the selected
following gap, ACC will adjust the
vehicle's speed and attempt to
maintain the follow distance gap
selected.
Press on the steering wheel to
adjust the following gap. When
pressed, the current gap setting
displays briefly on the instrument
cluster and HUD, if equipped.
Subsequent presses cycle the
button through three settings: Far,
Medium, or Near. The gap setting
will be maintained until it is
changed.
Since each gap setting corresponds
to a following time (Far, Medium,
or Near), the following distance will
vary based on vehicle speed. The
faster the vehicle speed, the further
back your vehicle will follow a
vehicle detected ahead. Consider
traffic and weather conditions when
selecting the following gap. The
range of selectable gaps may not be
appropriate for all drivers and
driving conditions.
Changing the gap setting
automatically changes the alert
timing sensitivity (Far, Medium,
or Near) for the Forward Collision
Alert (FCA) feature. See Forward
Collision Alert (FCA) System 0 234.
Alerting the Driver
Without Head-Up Display
With Head-Up Display
If ACC is engaged, driver action
may be required when ACC cannot
apply sufficient braking because of
approaching a vehicle too rapidly.
Driving and Operating
When this condition occurs, six red
lights or the collision alert symbol on
the HUD, if equipped, will flash on
the windshield, and either eight
beeps will sound from the front,
or both sides of the Safety Alert
Seat will pulse five times. See
Collision/Detection Systems under
Vehicle Personalization 0 155.
See Defensive Driving 0 183.
Approaching and Following a
Vehicle
The vehicle ahead symbol is in the
instrument cluster and HUD,
if equipped.
The vehicle ahead symbol only
displays when a vehicle is detected
in your vehicle s path moving in the
same direction.
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