LG TV C2 OLED BLACK SCREEN SOUND WORKING General Troubleshooting

Main PCA (Main Board)

The Main Board is responsible for processing video data and generating the On-Screen Display (OSD). Since the audio is functioning, the SoC is active, but a failure in the video output stage or the V-by-One transmitter prevents image data from reaching the panel. This is the primary component to replace when UI/Menus are also invisible.

Power Supply (PSU) Board

OLED panels require specific high-voltage rails to drive pixel emissivity. If the Power Supply fails to provide these specific voltages while still providing the 12V/13V logic power used by the Main Board for audio and SMART functions, the screen will remain black despite the TV being 'on'.

Internal Ribbon Cable Set (LVDS/V-by-One)

These cables transfer high-speed video data from the Main Board to the panel's timing logic. If the cables become unseated or suffer from pin corrosion/oxidation, the handshake between the board and panel fails, resulting in a black screen while the audio (which travels via a different path) remains unaffected.