so you getting a constant droning noise
sound like the drain pump is running
if that’s the case the most likely problem is a flooded base. below the floor of the dishwasher where all the motors and work are is a polystyrene float. its job is to detect leaks. if there is a leak and the bas fills up this float aborts the programme and turns the pump on. Nothing will happen apart from the drain pump till this water is removed
unplug appliance, remove the lower cover under the door. if there is water in ther mop it out being careful not to get any electrical components wet. then run appliance with the cover off while watching for leaks with a torch
if no leaks replace cover and see how things go.
Dave