The problem has developed recently. When I turn on the car the touchscreen flashes for a split second and then remains blank with its backlight on. If I press the screen it makes beeps. If I turn the cars lights on the screens backlight turns off but screen is still blank. I have checked all fuses and they are good. I have tried resetting by holding phone and menu button, it makes 2 beeps but still no visual. I read online it could be a loose wire. Does anyone have any advice before I bring it to my dealership and they charge me a fortune for a new screen. Any help would be appreciated. Thanks in advance.

 

If you don't want to do it yourself take it to a good auto electrician, will be cheaper than a dealer.
Could be just a bad connection also used screens are available.

 

It is unlikely a loose wire. Either your screen is bad or your nav unit - neither is a good choice. The writes to the screen are R,G,B and sync signal. If any of the colors are loose you get picture with that color missing. If the sync is loose - you will get some scrolling garbage on the screen. You can get all 3 colors loose at the same time, but how likely is that.

There are two more wires for the touch screen control and if those are lose you get ERROR-51 on the climate control screen.

Try the following procedure:
Press in the following order: [NAV] → [Up Arrow] →[NAV] → [Up Arrow] → [NAV] → [Up Arrow] → [Audio]→ [Audio] → [Audio]
The diagnosis menu screen should appear on the display. If that works it means your nav unit is not sending proper signal.

I'm attaching a reference to the screen diagnostic procedure.

 

Btw. ebay is a good source for used screens or nav unit, niether is very cheap, but chump change compared to OEM Jag part.