In short
LG OLED HDMI no signal means the selected input shows no source — often cable, wrong port, HDCP, device off, or bad sender — not automatically the power supply board.
Check AV first. Only with a dead set, blink codes or standby failures might the power supply board be involved — then stays black / repair.
AV checklist
Practical:
- Other certified HDMI cable
- Other TV HDMI input
- Test source on another display
- Select input manually
- Simple 1080p mode on player
- Deep color off briefly
When the power supply board is worth a look
Pure AV/software: cable, settings or updates. Dead or standby LED off: standby LED off, mainboard or power supply board.
AmparioWeb
We specialize in power supply boards and mainboards. Pure HDMI: support. Dead set: repair or parts.
Frequently asked questions
- Is the power supply board dead?
- Unlikely for HDMI-only. Check AV first.
- Which cable?
- Short, certified, matching bandwidth (4K/HDR).
- eARC port?
- For soundbars; video often better on other ports. See eARC no sound.
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Power boards for LG OLED — tested under load, 12-month warranty.
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