2012 Chrysler 300 Owner Manual - Page 217

UNDERSTANDING THE FEATURES OF YOUR VEHICLE 215 When the condition that deactivated the system is no longer present, the system will return to the "Adaptive Cruise Control Off" state and will resume function by simply reactivating it. NOTE: Installing a vehicle front-end protector or an aftermarket grille or modifying the grille is not recommended. Doing so may block the sensor and inhibit ACC operation. ACC Unavailable Warning If the system turns off, and the EVIC displays "Adaptive Cruise Control (ACC) Unavailable", there may be a temporary malfunction that limits ACC functionality. Although the vehicle is still drivable under normal conditions, ACC will be temporarily unavailable. If this occurs, try activating ACC again later, following a key cycle. If the problem persists, see your authorized dealer. 3 Adaptive Cruise Control (ACC) Unavailable Warning Service ACC Warning If the system turns off, and the EVIC displays "ACC/ FCW Unavailable Service Radar Sensor", it indicates there is an internal system fault. Although the vehicle is still drivable under normal conditions, have the system checked by an authorized dealer.