TV turns on or off by itself (HDMI-CEC, mobile power-on)

Most phantom power events come from HDMI-CEC (Samsung Anynet+, LG SimpLink): a connected device sends a power command. Network 'power on' features and a damaged cord are the other causes.

Cross-checked ~20 min easyBrands: Samsung, LG, All

Before you start

Check the power cord for damage; replace a damaged cord, do not tape it.

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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