My sister's d3 screen shows a snowy picture like a tv with no signal when she powers on the car. The sounds works and the touch screen works as well but she can't see what she is touching on the screen.

 

Any solutions or ideas on how to fix this or what may be causing it?

Does it do that no matter what source is being used? Is it constantly like that no matter what you do to it?

 

First thing I would do is to try resetting the unit. Power on the car, then hold the reset button on the top left of the face for a few seconds to reset it.

 

I can't think of anything external or setting related that would cause that... If it's a constant thing. Most likely something is broken or a loose connection internally. If so, you would probably have to send it in for service if it's still under warranty.