LG CX Power Failure Due to HDMI-CEC SimpLink Conflicts

Confirm this cause by disconnecting all HDMI cables from the television. If the TV successfully powers off using the remote or physical button while no HDMI devices are connected, the issue is confirmed as a signal conflict. Specifically, observe if an external device like a console or set-top box is sending a wake-up signal through the HDMI-CEC protocol, which forces the television to remain in an active power state.

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