Chosen Solution

Tohiba led tv has sound, back lights and blue screen but no picture or menu. Replaced main board but problem remains. Voltages on power supply board seem ok.

one of the video/audio cords not plugged in?

T-con board failure check the 24 v return coming from power supply to main logic board l(HDMI and cable hook up board )not the 24 v feeding the backlighting since it has sound there’s a better chance its not the main logic