Jeep Grand Cherokee 2013 Owner's Manual page 249

Using ACC On Hills
When driving on hills, ACC may not detect a vehicle in
your lane. Depending on the speed, vehicle load, traffic
conditions, and the steepness of the hills, ACC perfor-
mance may be limited.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 247
Lane Changing
ACC will 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 will not detect a vehicle until
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