TV won't turn on (standby light only, or blinking)

Separate power-delivery problems (outlet, surge strip, remote) from internal failures. A steady standby light with no response is often remote or button related; a blinking light after a clean power cycle on a good outlet is a hardware fault, usually the power supply board.

Cross-checked ~45 min moderateBrands: All

Before you start

TV power supply boards hold dangerous voltage after unplugging. Internal work is for trained techs only: unplug, wait, and discharge primary capacitors before touching.
Never open or flex an OLED panel.

Diagnostic steps

Unlock all 5 steps with expected values

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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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