GMC Cadillac XT4 2019 Owner's Manual page 209

208 DRIVING AND OPERATING
When it is determined that there is no
vehicle ahead or the vehicle ahead is
beyond the selected following gap,
then the vehicle speed will increase to
the set speed.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster 0 124.
The increment value used depends on
the units displayed.
Reducing Speed While ACC is at a
Set Speed
If ACC is already activated, do one of
the following:
Use the brake to get to the desired
lower speed. Release the brake and
move the thumbwheel down
toward SET . The vehicle will
now cruise at the lower speed.
Hold the thumbwheel down
toward SET until the desired
lower speed is reached, then
release it.
To decrease the vehicle speed in
smaller increments, move the
thumbwheel down toward SET to
the first detent. For each press, the
vehicle goes about 1 km/h (1 mph)
slower.
To decrease the vehicle speed in
larger increments, move the
thumbwheel down toward SET to
the second detent. For each press,
the vehicle speed decreases to the
next 5 km/h (5 mph) mark on the
speedometer.
To decrease speed while the
vehicle is stopped, move the
thumbwheel down toward SET
until the desired set speed is
displayed.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster 0 124.
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 and HUD. 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 0 221.