# HDMI-CEC for digital signage: switch screens on and off without a remote > Canonical HTML: https://screenrig.ai/guides/hdmi-cec-digital-signage HDMI-CEC (Consumer Electronics Control) is a control channel in the HDMI cable that lets one device tell another to turn on, go to standby or switch input. For signage, the player can switch the TV off at closing and on in the morning with no remote. It works only when the TV, the cable path and the player all support it. Updated November 11, 2026. Check each of the three before you rely on it. This guide shows how. Before you schedule anything, ask whether the screen can switch the TV at all. This is a real, read-only session on our own test screen, an onn 4K Streaming Device, run on 9 November 2026 through the screenRIG MCP server: > **You:** Can the ONN Test Rack switch its TV off over HDMI-CEC tonight? > > **Agent:** No. Its Player declares one display power method, an on-screen blackout, and not HDMI-CEC, so it can black the picture out but cannot put the TV into standby. It has no display schedule, and its display is set to on. The Player last reported the display as off at 08:54 Vancouver time while screenRIG asks for on, so the TV was turned off outside screenRIG, at the set or by its own power saving. For HDMI-CEC, use a Raspberry Pi, a Linux PC or a BrightSign player. ## How HDMI-CEC works CEC is a single shared wire in every HDMI cable, separate from the video signal. Devices on it send short messages to each other: "standby", "I am the active source", "power status?". The wiring is mandatory in HDMI, but a device does not have to implement CEC, which is why it works on one TV and not the next ([Wikipedia](https://en.wikipedia.org/wiki/Consumer_Electronics_Control)). Two messages matter for a sign: - **One Touch Play** (image view on). The player says it is the active source, and the TV turns on and switches to its input. - **System Standby.** The player tells the TV to go to standby. ## HDMI-CEC goes by other names TV makers rename CEC in their menus. If you cannot find "CEC", look for the brand's name ([Wikipedia](https://en.wikipedia.org/wiki/Consumer_Electronics_Control)): | Brand | Name in the menu | | --- | --- | | Samsung | Anynet+ | | LG | SimpLink | | Sony | BRAVIA Sync, BRAVIA Link or Control for HDMI | | Philips | EasyLink | | Panasonic | VIERA Link, HDAVI Control or EZ-Sync | | Sharp | Aquos Link | | Toshiba | CE-Link or Regza Link | | Hisense, Vizio | CEC | Turn it on in the TV's settings, usually under General, External devices, or HDMI. ## Why HDMI-CEC stops working Most "CEC is broken" reports come down to one of these: 1. **It is off on the TV.** Many TVs ship with it off, and a factory reset or firmware update can turn it off again. 2. **Something sits in the middle.** HDMI switches, splitters, extenders and AV receivers commonly block or rewrite CEC. Plug the player straight into the TV. 3. **The TV ignores wake-up in deep standby.** Some TVs drop CEC in their lowest power mode. Look for a quick-start or network-standby setting, and test a full overnight cycle before you trust it. 4. **Another device grabs the TV.** A soundbar, console or second player on the same TV can send its own CEC commands and switch the input away. 5. **The player cannot send CEC.** Many streaming sticks and Android boxes do not let an app send CEC commands at all. The only real test is to schedule an off and an on, leave it overnight and look at it in the morning, or ask your agent for a screenshot and the power the player reports. ## Which players can switch a TV with HDMI-CEC On screenRIG every Player declares the display power methods it can use, and your agent reads them before it acts. From the [Player guide](https://screenrig.ai/docs/players.md#device-control): | Player | How it switches the display | | --- | --- | | Raspberry Pi and Linux | HDMI-CEC with a CEC device and `cec-ctl`, DDC/CI where `ddcutil` finds the monitor, the panel backlight, or an on-screen blackout | | BrightSign | HDMI-CEC through the BrightSign shell, or an on-screen blackout | | Android (managed, device owner) | The backlight, HDMI-CEC on a privileged install, or an on-screen blackout | | [Windows](https://screenrig.ai/digital-signage/windows.md) | DDC/CI where the monitor answers, monitor off, or an on-screen blackout | | ChromeOS kiosk (web Player) | The display's RS-232 control port through a USB serial adapter, for Samsung, LG, NEC and Philips displays | | Android from Google Play, Amazon Signage Stick, Apple TV, [Samsung Tizen](https://screenrig.ai/digital-signage/samsung-tizen.md), [LG webOS](https://screenrig.ai/digital-signage/lg-webos.md) | An on-screen blackout | An on-screen blackout is not CEC: the screen goes black but the panel stays powered. It still hides the content out of hours, and it works on every Player. The Player reports the power it actually achieved, so you can tell "the TV is off" from "we asked the TV to turn off". ## Schedule screens on and off A display schedule lists up to 16 windows when the display is on, in the screen's timezone. Outside every window the display goes to standby. The Player evaluates the schedule on the device, so it keeps working offline. Ask your agent in a sentence, or set it with the CLI: ```json {"enabled": true, "windows": [{"days": ["mon", "tue", "wed", "thu", "fri"], "start": "07:00", "end": "19:00"}, {"days": ["sat"]}]} ``` ```bash screenrig screen display-schedule set --tag Cafe --file hours.json ``` For a one-off, such as a late event, `screen display` overrides the schedule until its next boundary or for a set time: ```bash screenrig screen display --tag Lobby --power on --for 3h ``` The [CLI reference](https://screenrig.ai/docs/cli/device.md#device) covers display schedules, overrides and the health each Player reports. ## Beyond on and off: fixing a screen without a site visit Turning a screen off is half of it. The other half is getting a stuck screen back without a ladder. A Player that declares the capability can be told to: - **Reboot the device**, on Raspberry Pi and Linux kiosk installs, BrightSign, Windows and managed Android. A reboot sent to an offline screen waits, queued, for up to 24 hours and runs when the screen comes back. - **Restart the Player app** without rebooting the device. - **Clear its cache**, keeping its pairing and settings, and download its content again. Scheduled reboots, such as every night at 04:00 in the screen's timezone, come with every plan. You also hear about trouble without watching a dashboard: every project starts with an email to its owner when a screen has been offline for 10 minutes, and notifications can watch for a disconnected display, a device running hot, a Player that keeps crashing, or a screen showing a blank or frozen picture. ## Frequently asked questions ### Should HDMI-CEC be on or off for digital signage? On, if your player can use it and you want the screen switched off out of hours. Turn it off if another device on the same TV keeps switching inputs or waking the screen. ### Is HDMI ARC the same as HDMI-CEC? No. ARC (Audio Return Channel) sends sound from the TV back to a soundbar or receiver. CEC sends control commands. They often sit in the same menu, and a soundbar on ARC usually takes its volume commands over CEC, but they are different features. ### How do I tell if my TV has HDMI-CEC? Look in the TV's settings for CEC or the brand's name for it (the table above). If the menu has it, the TV implements CEC. Then test it with your player before you mount the screen. ### Can an Amazon Signage Stick turn the TV off? With screenRIG, the Amazon Signage Stick blacks out the picture on a schedule that runs on the device, even offline. That is not a CEC command, so the panel stays powered. Use a Raspberry Pi, a Linux PC or a BrightSign player when you need the TV itself switched off. ## Sources - [en.wikipedia.org/wiki/Consumer_Electronics_Control](https://en.wikipedia.org/wiki/Consumer_Electronics_Control) - [screenrig.ai/docs/players](https://screenrig.ai/docs/players) - [screenrig.ai/docs/cli](https://screenrig.ai/docs/cli) ## Related - [Digital Signage Player: How to Choose One](https://screenrig.ai/guides/digital-signage-player.md): A digital signage player is the device that plays content on a screen. Compare Pi, BrightSign, sticks and PCs; the screenRIG Player is free. - [Raspberry Pi Digital Signage Software and Setup](https://screenrig.ai/digital-signage/raspberry-pi.md): Run digital signage on a Raspberry Pi 5 or 4: what to buy, setup from a blank card to a pairing code, kiosk boot, offline play and video walls. - [Free BrightSign CMS and Digital Signage Software](https://screenrig.ai/partners/brightsign.md): BrightSign players run free screenRIG software from an SD card, with your AI agent as the editor. Copy one download, power on and pair. - [How to Turn a Smart TV Into Digital Signage](https://screenrig.ai/guides/smart-tv-digital-signage.md): Turn a smart TV into digital signage with the screenRIG Player: install it on the TV, open it in its browser, or add a stick. Pick the route for your TV. - [Supported Players and Setup](https://screenrig.ai/docs/players.md): Install the screenRIG Player on your screen, pair it with your agent, and compare content types, streams and device controls by platform. ## More guides - [Google Slides Digital Signage on Any TV](https://screenrig.ai/guides/google-slides-on-tv.md): Ask your AI agent to put Google Slides on a TV. Slides replay offline and one changed slide updates fast. - [PowerPoint Digital Signage: Play a Deck on a TV](https://screenrig.ai/guides/powerpoint-on-tv.md): Use PowerPoint as digital signage: export the slides, size them for a 1080p or 4K TV, and have your AI agent play the deck in a loop. - [Display a Google Sheet on a TV](https://screenrig.ai/guides/google-sheets-on-tv.md): Ask your AI agent to put a Google Sheet on a TV and keep it current. Updates land in seconds, with no cast tab or public link. - [Publish Content to a TV Programmatically](https://screenrig.ai/guides/publish-content-to-tv-programmatically.md): Publish to a TV from code, a CI job or your AI agent, with proof it is playing. See the conversation first, then the short script. - [All guides](https://screenrig.ai/guides.md): Put a sheet, slides, a dashboard, a website or a camera on a TV by asking your AI agent. Each guide shows what to say and what to expect. [Start free](https://screenrig.ai/docs/start.md). screenRIG is free.