Jeep 2012 Grand Cherokee Owner's Manual page 225

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 will not be suffi-
cient distance to the vehicle ahead.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 221
Stationary Objects And Vehicles
ACC does not react to stationary objects and stationary
vehicles. For example, ACC will not react in situations
where the vehicle you are following exits your lane and
the vehicle ahead is stopped in your lane. Always be
attentive and ready to apply the brakes if necessary.
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