Owner's Manual
Page 76
... those recommended because this can affect the normal operation of ACC. Do not use ACC when towing a trailer with the radar signals Action Clean the grille surface in front of the radar or remove the object causing the obstruction Wait a short time. Failing to do so may not detect, warn, or... not detect, warn, or respond to potential collisions. Driver Controls Cause The surface of the radar in the grille is dirty or obstructed in some way The surface of the radar in the grille is clean but the message remains in the display Heavy rain or snow is interfering with brake controls...
... those recommended because this can affect the normal operation of ACC. Do not use ACC when towing a trailer with the radar signals Action Clean the grille surface in front of the radar or remove the object causing the obstruction Wait a short time. Failing to do so may not detect, warn, or... not detect, warn, or respond to potential collisions. Driver Controls Cause The surface of the radar in the grille is dirty or obstructed in some way The surface of the radar in the grille is clean but the message remains in the display Heavy rain or snow is interfering with brake controls...