RAM 2500 2019, Owner'S Manual, Page: 376 / 696

374 STARTING AND OPERATING
Lane Changing
ACC may not detect a vehicle until it is completely in the
lane in which you are traveling. In the illustration shown,
ACC has not yet detected the vehicle changing lanes and it
may not detect the vehicle until it's too late for the ACC
system to take action. ACC may not detect a vehicle until it
is completely in the lane. There may not be sufficient
distance to the lane-changing vehicle. Always be attentive
and ready to apply the brakes if necessary.
Lane Changing Example
Narrow Vehicles
Some narrow vehicles traveling near the outer edges of the
lane or edging into the lane are not detected until they have
moved fully into the lane. There may not be sufficient
distance to the vehicle ahead.
Narrow Vehicle Example