y33 cima touch screen help needed!

[sldwys]

Hey guys - I took my car into the panel beaters a couple of months ago - Had the rear window replaced and a repaint. Since I got it back the touch screen display would flick off and on for a few days then lost all display. I have checked all fuses I could find, and have checked the actual screen itself ( Screen itself powers up when you plug it in, And I have tested it with a known working screen also.
I have no heaters, I have nothing! And am tyrying to sell the car.

Anybody know what causes the screens to have no picture at all ?

1997 fgdy33 Cima.