Hello, I'm trying to repair an LG OLED65C7V-Z that has no picture and no sound. When I plug the TV, I hear the relay click. When I push the power button, i hear a second click and there are 3 red blinks but no sound and no picture.
I checked the voltage at the power board and I have the 20V and 12V at the mainboard connector, I have the 12V at the T-CON connector but not the 24V.
I tested the power supply without the T-CON and the main board by injecting 3.3V into the PWR_ON pin, the DPC pin and the 12VT_ON pin but still no 24V.
I checked the fuses, the diodes, the capacitors and I checked for shorts circuit on the power board and T-CON but nothing strange. The big transformer (in red) has 53V at his inputs but nothing at his outputs. The transistor (in blue) has 10 V between the middle pin and the others while the transistor right next to him has 110V, I checked the transistor in blue out of the circuit and he is fine. I checked the temperature with IR cam and nothing above 50°C.
I don't know if it is the T-CON board or the power board that has failed and if it is the big transformer (in red) that has failed.
Already thank you for your help and sorry for my English, I'm not speaking english regularly.
I checked the voltage at the power board and I have the 20V and 12V at the mainboard connector, I have the 12V at the T-CON connector but not the 24V.
I tested the power supply without the T-CON and the main board by injecting 3.3V into the PWR_ON pin, the DPC pin and the 12VT_ON pin but still no 24V.
I checked the fuses, the diodes, the capacitors and I checked for shorts circuit on the power board and T-CON but nothing strange. The big transformer (in red) has 53V at his inputs but nothing at his outputs. The transistor (in blue) has 10 V between the middle pin and the others while the transistor right next to him has 110V, I checked the transistor in blue out of the circuit and he is fine. I checked the temperature with IR cam and nothing above 50°C.
I don't know if it is the T-CON board or the power board that has failed and if it is the big transformer (in red) that has failed.
Already thank you for your help and sorry for my English, I'm not speaking english regularly.
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