GMC Sierra Owner's Manual page 264

Warning
The Park Assist system does not detect
children, pedestrians, bicyclists, animals,
or objects located below the bumper or
that are too close or too far from the
vehicle. It is not available at speeds
greater than 8 km/h (5 mph). To prevent
injury, death, or vehicle damage, even
with Park Assist, always check the area
around the vehicle and check all mirrors
before moving forward or backing.
The instrument cluster may have a Park
Assist display with bars that show distance
to object and object location information
for the Front and Rear Park Assist system.
As the object gets closer, more bars light up
and the bars change color from yellow to
amber to red.
When an object is first detected in the rear,
one beep will be heard from the rear,
or both sides of the Safety Alert Seat will
pulse two times. When an object is very
close <0.4 m (1.5 ft) in the vehicle rear or
<0.3 m (1 ft) in the vehicle front
continuous beep will sound from the rear or
front depending on object location, or both
sides of the Safety Alert Seat will pulse five
times. Beeps for FPA are higher pitched than
for RPA.
Rear Cross Traffic Alert (RCTA)
If equipped, when the vehicle is shifted into
R (Reverse), RCTA shows a red warning
triangle with a left or right pointing arrow
on the infotainment display to warn of
traffic coming from the left or right. This
system detects objects coming from up to
20 m (65 ft) from the left or right side of
the vehicle. When an object is detected,
either three beeps sound from the left or
right or three Safety Alert Seat pulses occur
on the left or right side, depending on the
direction of the detected vehicle.
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.
Driving and Operating
RCTA is disabled when the trailer connection
status is displayed.
RCTA can be turned off. See Collision/
Detection Systems under Vehicle
Personalization 0 132.
a
Turning the Features On or Off
Press 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. See Park
Assist under Vehicle Personalization 0 132.
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 vehicle personalization. The On
with Towbar setting allows Park Assist to
work properly with a trailer hitch. Some
larger trailer hitches may not be compatible.
263