'''++@mnm1982++'''
you can measure the output from your power board to the backlight LED’s etc. Since your TV does not come on but clicks you will have to check the power board voltages.Use your multimeter and check the voltage on the connectors according to the values printed on the board. Since you also have no backlight when your disconnect the main board from the power board it stands to reason that you have a bad power supply. Second suspect is the main board