A common failure of this TV is a blown fusible resistor on the power supply.  There are three rectangular cement resistors at the corner of the board –  R927, R928 and R929  They should be marked 10 ohm and 5W.  They can be measured in circuit though out of circuit is more accurate.  All three should be replaced though typically only one blows..

Equivalent part can be obtained from Digikey part number TWW5J10RE-ND