The logo comes up for a couple of seconds then blank screen, picture can be seen with a torch and there's sound.
A spare LED strip was tried in place if the panel LED'sand that flashed ON and then OFF. The leds are switched by a FET on the earthy side, the top side of the FET there's voltage and drives the test strip.... so something is telling the lamp switch to turn off.
Would you cast eyes on the panel LED's or elsewhere, firmware, Tcon and suchlike - the Tcon fuse is OK.... the LEDs have zener diodes across each one.
Thanks Dave.