No any response on touch screen buttons of Toyota RAV4 2014. Please help!

Hello, The touch screen, as all functional buttons on the radio, is completely controlled from within the radio. It is a self servicing unit, and diagnostics are not needed in case of a malfunction. Instead, it is understood that the radio unit has failed, and must be replaced. Before considering it has failed, however, you can ask the dealership if software updates are available, and try removing the fuse, waiting about 15 minutes, and reinstalling the fuse. This sort of 'hard reset' may cause the radio to reboot with full functionality.