GMC 2018 Acadia Denali Owner's Manual page 230

decreases to the next 5 km/h
(5 mph) mark on the
speedometer.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster 0 120.
The increment value used depends
on the units displayed.
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. Each press
cycles the gap button through three
settings: Far, Medium, or Near.
When pressed, the current gap
setting displays briefly on the
instrument cluster. 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 0 238.
Alerting the Driver
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 will flash on the windshield.
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 0 144.
See Defensive Driving 0 193.
Approaching and Following a
Vehicle
The vehicle ahead indicator is in the
instrument cluster.
The vehicle ahead indicator only
displays when a vehicle is detected
in your vehicle s path moving in the
same direction.
If this symbol is not displaying, ACC
will not respond to or brake for
vehicles ahead.
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