Match the symptom, then work through the safe checks.
1. What best matches what you observe?
2. Complete only the checks that are safe for you.
Show stop conditions
- A port is bent, burned, loose, or unusually hot
- Opening the TV or source device would expose internal power sections
Likely causes
- The wrong HDMI input is selected
- The source device is off, asleep, or not outputting video
- The HDMI cable, port, receiver, or adapter is failing
- The source resolution or HDCP handshake is incompatible
Quick checks, in order
Confirm the exact input number
Match the TV input to the physical port used by the cable.
Wake and restart the source device
Power-cycle both the TV and source, then connect directly.
Test another HDMI cable and port
Bypass receivers, switches, and adapters for one test.
Reset source video output
Use the source device’s safe-mode or low-resolution procedure if the screen stays blank.
What does the TV detect?
A cable, handshake, resolution, or power issue is likely.
Focus on the original source device and its output settings.
The TV input board, settings, or power state may require service.
Stop and get qualified help when
- A port is bent, burned, loose, or unusually hot
- Opening the TV or source device would expose internal power sections
Official support and model manuals
Use the full model number from the rating label. The manufacturer manual is the deciding reference when codes differ by region or product family.
Frequently asked questions
Can an HDMI cable fail while still looking normal?
Yes. Internal conductors or shielding can fail without visible external damage.
Why does no signal appear after changing resolution?
The source may be outputting a format the TV or receiver cannot display. Start the source in a safe or low-resolution mode.