Sony TV Model KP-53XBR35 Power Supply problems

[Bigaltoo]

Have been troubleshooting captioned for several hours. All DC voltages are either low or zero. Cannot locate short. Power transformer primary voltage is 62 AC which seems low.
Haven't serviced TV's in several years. Schematic states all voltages taken from ground unless noted to contrary. Primary and secondary seem to have separate grounds although symbols the same (????). Advice and suggestions please. Cordially, Alan

[Neo]

I`m working on the power supply of a TV Sony and in the diagram and Board it`s written THP651, it`s a little black box with three terminals and I don`t know what is it? Somebody know?

[Guest]

What do you mean by the power transformer?

The primary ground needs to be isolated from the secondary ground for safety reasons. Make sure you are measuring from the correct ground on a component. Most heatsinks are not at ground potential.

There should be nearly 320 Volts dc across the mains capacitor, if not check the bridge rectifier.

[gary]