My 2008 Toyota Sienna Navigation is not working?

Hello, I have a 2008 Toyota Sienna Limited and it is equipped with navigation. Today, it is not working and I have a sense it is the power because when there is no response every time I press a navigation related on. When in reverse, the camera does not turn like it usually does. When I turn on the headlamps, the ons around the navigation only are not turned on. Can you give me advice on how to fix this problem? Thanks.