- TVs
- Smart TV
No Signal
Samsung "No Signal" on Smart TV: the selected input is not receiving a picture
Risk level
Low
Usually safe to check without specialist tools.
Urgency
Low
Quick answer
The TV is not receiving a signal on the selected source. Check that the external device is on, that the TV and the device use the correct source, and that the cables are firm and in the right ports; then try a new cable.
Safety first
Stop and check this first
- Before booking a repair, try another device and another cable on the same source: Samsung only treats the TV as faulty when two different devices fail.
Safe checks you can perform
- Device on and correct source
- Cable connections
- Replace the cable
- Another device on the same source
Leave these tasks to a qualified professional
- Do not attempt this professional task: External device check
- Do not attempt this professional task: Samsung service
What a technician must be able to justify
A technician is coming
These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.
These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.
External device check
What they doIf a different device works on the same source, the maker of the original device checks its HDMI output.
They must show youthe video output working on another screen.
In writingthe repair or setting applied.
Samsung service
What they doIf two different devices fail on the same source after every step, a technician tests the TV inputs with a known good device.
They must show youthe input test.
In writingthe diagnosis and any replaced part with its reference.
Before accepting a part or repair
Nothing has been shown yet. Do not accept a part swap based on the code alone.
Checks and evidence, step by step
Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.
- 1
Device on and correct source
No special tools
Procedure
- Who:
- you.
- How:
- confirm the external device is turned on. Check the TV source and the source on the external device, since cable boxes and home theater systems can have several.
- Result that matters:
- whether the picture appears with the right source.
- If it appears:
- the source or the device power was the cause.
- If it stays:
- check the cable connections.
- Evidence to keep:
- the HDMI port number in use.
Evidence: Samsung TV or projector shows an error message
- 2
Cable connections
No special tools
Procedure
- Who:
- you.
- How:
- make sure every connection is secure and in the correct port on both the TV and the device.
- Result that matters:
- whether the picture comes back after securing the cables.
- If it does:
- a loose connection was the cause.
- If it does not:
- replace the cable.
- Evidence to keep:
- which ports you used.
Evidence: Samsung TV or projector shows an error message
- 3
Replace the cable
No special tools
Procedure
- Who:
- you.
- How:
- replace the connection cable with a new one. For 4K at 120Hz use a certified HDMI 2.1 cable; Samsung notes some lower quality HDMI 2.1 cables still cause issues.
- Result that matters:
- whether the picture appears with the new cable.
- If it does:
- the original cable is defective.
- If it does not:
- test another device on the same source.
- Evidence to keep:
- type of the failing and the working cable.
Evidence: Samsung TV or projector shows an error message
- 4
Another device on the same source
No special tools
Procedure
- Who:
- you.
- How:
- connect a different external device to the same source.
- Result that matters:
- whether the new device displays.
- If it does:
- the issue is with the original device; contact its maker.
- If neither works after all the steps:
- the TV requires service; request it from Samsung.
- Evidence to keep:
- models of both devices and the result.
Evidence: Samsung TV or projector shows an error message
Where this code applies
A code is meaningful only inside the right product and version context.
Primary scope
- System
- TVs
- Brand
- Samsung
- Product type
- Smart TV
Known code variants
- Cable HDMI desconectado
- LG TV no signal
- mensaje no hay señal LG
- No hay señal
- Samsung TV no signal
- Señal débil
- Sin señal
- Weak Signal
What it means
Samsung shows "No Signal" or "Weak Signal" when the selected input is not receiving a picture. Usual causes are an external device that is off, the wrong source on the TV or on the device (cable boxes and home theater systems can have several), a loose or faulty cable, or the device itself. For 4K at 120Hz Samsung requires a certified HDMI 2.1 cable. Samsung only says the TV needs service when two different devices fail on the same source after every step.
Warnings and stop conditions
- Loweditorial warning
Before booking a repair, try another device and another cable on the same source: Samsung only treats the TV as faulty when two different devices fail.
Evidence: Samsung TV or projector shows an error message
Symptoms and causes
Probable causes · in order
- External device offCommon
The device is off; the message goes away when it is turned on.
Evidence: Samsung TV or projector shows an error message
- Wrong sourceCommon
The TV source does not match the port used, or the cable box or home theater system has another source selected.
Evidence: Samsung TV or projector shows an error message
- Loose or faulty cablePossible
The message goes away after reseating or replacing the cable; at 4K 120Hz a cable that is not certified HDMI 2.1 can fail.
Evidence: Samsung TV or projector shows an error message
- Fault on the external devicePossible
A different device works on the same source; the issue is with the original device.
Evidence: Samsung TV or projector shows an error message
- TV inputLess common
Two different devices fail on the same source after every step; this is the only case where Samsung calls for service.
Evidence: Samsung TV or projector shows an error message
Virtual technician
Does No Signal still appear after these checks?
Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.
Sources and technical references
- 1
Samsung TV or projector shows an error message
Samsung · 2026 · official_doc
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