2015 Cadillac ATS Owner Manual - Page 271

9-48 Driving and Operating Do not use ACC when driving on steep hills or when towing a trailer. ACC will not detect a vehicle in the lane while driving on steep hills. The driver will often need to take over acceleration and braking on steep hills, especially when towing a trailer. If the brakes are applied, the ACC disengages. Ending ACC There are three ways to disengage ACC: ... Other Vehicle Lane Changes Cleaning the Sensing System The camera sensor on the windshield behind the rearview mirror and the radar sensors on the front of the vehicle can become blocked by snow, ice, dirt, or mud. These areas need to be cleaned for ACC to operate properly. For cleaning instructions, see "Washing the Vehicle" under Exterior Care on page 10-78. System operation may also be limited under snow, heavy rain, or road spray conditions. ACC will not detect a vehicle ahead until it is completely in the lane. The brake may need to be manually applied. Do Not Use ACC on Hills and When Towing a Trailer Step lightly on the brake pedal. *. Press J. Press Erasing Speed Memory The cruise control set speed is erased from memory if J is pressed or if the ignition is turned off.