hi
first connect the tv to a satellite receiver or dvd then follow instructions bellow:
is the sound still ok after image goes off? if yes then do this:
check for 24vdc if it still reaches the inverter board, if yes then the problem is in the inverter section...
if all the tv functions shutsdown then suspect a defective power supply...
1:inverter troublshooting: cheeck all the fuses and fet transistors and chopers for open circuit, open-circuited ccfl could cause the inverter board to go down, if found fuses to be shorted then it could be due to life span or due to short circuit in mosfets or choppers ..if mosferts found bad then replace them and check everything on inverter board to prevent replacement parts from being damaged again...if the problem is found to be opned ccfl lamp then provide me with the inverter controller ic part number so that i can tell how to remove the protection and force the inverter board to function even if there is open ccfl lamp
2:psu problem
check for bulged capacitors shorted secondary output diodes, power ic, smpt...
good luck