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Video / HDMI

Projector or display shows 'No Signal' over HDMI

'No Signal' means the display isn't receiving a valid HDMI stream it can lock to. The cause is almost always one of three things: the handshake (EDID/HDCP), the physical link (cable/extender), or the source output settings.

1. Test the handshake with a direct cable

Bypass every matrix, extender, and switcher: run a single known-good HDMI cable straight from the source to the display. If the image appears, the problem is in the signal chain (an extender or switcher), not the source or display.

2. Suspect EDID first in AV systems

  1. 1EDID is how the display tells the source what resolutions it supports. Through switchers and extenders, EDID often gets lost or defaults to something the source can't match.
  2. 2Set a fixed EDID on the switcher/extender (e.g. 1080p60 or 4K30) matching the display's native capability.
  3. 3Power-cycle the source after changing EDID so it re-reads capabilities.

3. Check HDCP compatibility

Protected content (and some sources) require HDCP all the way through. One non-HDCP-compliant device in the chain — or an HDCP version mismatch (2.2 vs 1.4) — produces a black screen or 'No Signal'. Confirm every device in the path supports the required HDCP version.

4. For HDBaseT extenders, verify the link

Over Cat cable, a marginal or too-long run causes intermittent 'No Signal'. Check the extender's link LED, keep runs within spec, and use solid-core shielded cable terminated correctly. Sparkles or dropouts point straight at the cable.

Frequently asked

Why does it work sometimes and not others?

Intermittent 'No Signal' is usually a marginal cable/extender link or an HDCP re-negotiation failure on source wake. Test the physical link first.

Should I set EDID manually?

In any system with switchers or extenders, yes — a fixed EDID prevents the source from guessing wrong when the display isn't directly connected.