When we have taken this vehicle on the highway or interstate, the Adaptive Cruise Control randomly disengages while driving and renders any cruise options unusable. When this happens the vehicle brakes hard while driving. The braking system also randomly brakes hard while driving, even if the cruise control is working. This is a huge safety concern as we are on the highway and interstate with several other vehicles around us. We are worried we will get in an impact collision from the rear. We have taken this vehicle to a certified Honda repair center four times for this specific concern and this 4th occurrence, the Pilot has been there for over 27 days with no resolution. This is a brand new vehicle and we have had this safety issue/faulty ACC since we purchased it.