No Signal on HDMI? Fix “No Input” on a 4K QLED TV

Few things are more annoying than sitting down to play or stream, only to see “No Signal” or “No Input” on your TV. The good news is: in most cases, this is not a hardware failure. It’s usually a handshake issue—HDMI settings, port selection, cable stability, or device output modes.

This guide is a practical, step-by-step troubleshooting flow you can follow in 10–15 minutes. It’s written for real setups: consoles, streaming boxes, PCs, and soundbars connected via eARC.

1) Start with the fastest checks (60 seconds)

Check A: Are you on the correct HDMI input?

It sounds obvious, but many “No Signal” issues are simply the TV being on the wrong input—especially when you have multiple devices connected.

• Use the TV remote “Input/Source” button

• Select the exact HDMI port your device is plugged into

Check B: Wake the device properly

Some devices “sleep” in a way that confuses HDMI handshake.

• Power the device fully off and on (not just sleep)

• Unplug power for 10 seconds if it’s stuck

Check C: Try a different HDMI cable if you have one

A cable can pass 1080p but fail at 4K HDR or high refresh modes. Swapping the cable is the quickest way to eliminate that variable.

2) Understand why “No Signal” happens (simple explanation)

HDMI is not just a video pipe. It involves a “handshake” where the TV and device agree on:

• resolution (1080p / 4K)

• refresh rate (60Hz / 120Hz / 144Hz)

• HDR mode (HDR10 / etc.)

• copy protection rules (HDCP)

When the handshake fails, the TV may show “No Signal” even though the cable is connected.

3) The correct power-cycle order (fixes many handshake bugs)

If you only do one “advanced” fix, do this:

1. Turn off TV and device

2. Unplug both from power for 30 seconds

3. Plug in TV first and turn it on

4. Plug in the device and turn it on

5. Wait 10–20 seconds on the correct HDMI input

This forces a clean negotiation between TV and device.

4) HDMI port settings on the TV (the #1 hidden cause)

Many 4K QLED TVs require enabling a high-bandwidth mode per port, commonly called:

• Enhanced HDMI

• HDMI Enhanced Format

• High Bandwidth / 4K Enhanced

• Input Signal Plus

• HDMI 2.1 mode

If this setting is OFF, the device may try to output 4K HDR or 120Hz, and the TV rejects it—resulting in black screen or “No Signal.”

What to do

• Go to TV Settings → Inputs/HDMI

• Find the port your device uses

• Enable Enhanced/High Bandwidth mode

• Restart the TV if prompted

5) “No Signal” with consoles (PS5 / Xbox) — common fixes

Fix A: Lower the output temporarily

If the console is outputting a mode your TV can’t accept (or the handshake fails), force a safer mode:

• Set console output to 1080p temporarily

• Then switch back to 4K once signal is stable

Fix B: Disable optional features to test stability

When troubleshooting, turn OFF temporarily:

• VRR

• 120Hz mode

• HDR

If signal returns, re-enable features one by one. This identifies the exact feature causing the handshake failure.

6) “No Signal” with a soundbar (ARC/eARC path issues)

If your setup is:

• Device → TV (HDMI)

• TV → Soundbar (eARC)

The “No Signal” may not be video at all—sometimes soundbars can interfere with HDMI control and switching.

Fix order

1. Disconnect soundbar HDMI (eARC) temporarily

2. Connect device directly to TV and confirm signal

3. Reconnect soundbar and ensure it’s on the ARC/eARC port

4. Enable eARC in TV settings (if available)

Also check if HDMI-CEC is causing confusion (more below).

7) HDMI-CEC conflicts: when devices fight for control

HDMI-CEC allows devices to control each other (power on/off, input switching). It’s convenient—but can cause switching loops or wrong input selection.

Symptoms:

• TV switches inputs by itself

• device wakes but TV shows another input

• “No Signal” appears because TV got switched away

Quick test

• Turn off HDMI-CEC on the TV temporarily

• See if the problem disappears
  If it does, re-enable it later and disable CEC on the problem device only.

8) HDCP and streaming devices: the “black screen but sound works” clue

Some streaming services require HDCP (copy protection). If HDCP fails, you might see:

• black screen in one app

• menus work, but playback fails

• sound may still play

Fixes:

• swap HDMI cable

• use a different HDMI port

• power-cycle TV and device

• ensure the TV port is in the correct enhanced mode

9) When the TV shows signal but it’s unstable (flicker / dropouts)

If you get brief signal then lose it, suspect:

• cable quality

• unstable high bandwidth mode (4K HDR 120Hz is demanding)

• long cable run

• loose HDMI connection or bent port stress

Fixes:

• use shorter cable

• reduce bandwidth temporarily (4K60 first, then 120Hz later)

• ensure the cable is not tightly pulled behind the TV

10) A clean troubleshooting flow

1. Confirm correct HDMI input

2. Swap cable (fastest variable)

3. Power cycle TV + device (unplug 30 seconds)

4. Enable enhanced HDMI mode on the correct port

5. Disable VRR/120Hz/HDR temporarily

6. Test device on another HDMI port

7. Remove soundbar (eARC) temporarily to isolate

8. Disable HDMI-CEC temporarily

9. If streaming-only issue: suspect HDCP/app limitation