Enable Input Signal Plus on the right Samsung TV port
Turn on the enhanced HDMI mode only for the connected 4K or HDR source, then verify the source output and model-specific port limits.
Direct answer
The shortest reliable path.
On supported Samsung TVs, Input Signal Plus—called HDMI UHD Color on some older models—enables the selected HDMI input to accept enhanced 4K and HDR signals. Open Settings, General or Connection, External Device Manager, Input Signal Plus, then enable the exact HDMI port used by the source. The setting cannot add 4K, HDR, or 120 Hz to a port or TV that lacks that capability. Check the model manual for port-specific limits, especially when only one input supports the highest refresh rate.
System view
Check the whole path.
- 014K or HDR source
- 02Source output setting
- 03Compatible HDMI cable
- 04Selected Samsung HDMI port
- 05Input Signal Plus and picture mode
Scope before steps.
Samsung TVs with Input Signal Plus or HDMI UHD Color connected to a 4K, HDR, game-console, PC, or UHD playback source.
A complete Samsung model matrix, service-menu changes, panel calibration, HDMI cable certification, or a source that cannot output 4K or HDR.
Procedure
Do this in order.
- 01
Choose the capable port
Connect the source to the HDMI port documented for the required resolution, refresh rate, and gaming features.
- 02
Enable the selected input
Open Settings, General or Connection, External Device Manager, Input Signal Plus, and turn on the connected HDMI number.
- 03
Verify the source output
Set the console, PC, or player to automatic detection, then enable only formats the TV reports as supported.
- 04
Test content and status
Play known 4K HDR content or a supported game and inspect both source status and TV information.
Diagnostic matrix
Read the result, not the guess.
| What you see | Check next | What it means |
|---|---|---|
| Source reports that HDR or 4K is unsupported | Confirm Input Signal Plus is enabled for the actual connected port. | The enhanced capability may still be disabled on that input. |
| 4K works but 120 Hz does not | Check the model manual for which port and resolution combinations support 120 Hz. | Input Signal Plus does not override a physical port limit. |
| Picture disappears after enabling the setting | Return the source to automatic or a lower format and verify cable and source compatibility. | The connected device or path may not handle the enhanced signal reliably. |
Stop conditions
Know when not to keep changing things.
- Do not infer port capability from another Samsung model or screen size.
- Do not repeatedly hot-plug an unstable HDMI path when the equipment instructions require power-off connection.
- Do not enter the service menu to solve a normal input-format problem.