"I would like to know what are the currents in the 3V3, 5V, 12V and 24V voltages of the LED Tvs?"
There is a specification for each type of TV, as the currents depend on the circuits found in them, the size of the screen and several other factors. This information is usually in the possession of the device manufacturer and it is not simple to obtain, as they limit the information to authorized workshops that normally have specific diagnostic modes, and in most cases only exchange boards.
