jvc lt40c550 washed out flashing screen not backlight

so i bought this TV to use for a microscope monitor knowing it had the fault (that's the fun part the screen is faded you can just about see the image and some time it flashes black the led back light is fine, iv got 12v and 5v with no ripple at the tcon/driver board. iv seen post suggesting the main psu is at fault but i doubt that as the tv boots fine my money is either the main board ie needing a reball as the data lines are failed mor more likely something on the driver/tcon board any suggestions or advice would be great.

I usually work on audio equipment, so this is new territory for me.

Thanks in advance