LG TV via Serial

The LG TV via Serial integrationIntegrations connect and integrate Home Assistant with your devices, services, and more. [Learn more] lets you control LG TVs by connecting to their RS-232 serial port. By connecting the TV to your Home Assistant server using a serial (RS-232) cable, an ESPHome-based serial proxy, or a USB-to-serial adapter, you get local control of the TV.

Controlling a TV via RS-232 is more reliable and responsive than using the TV’s network or IR interfaces, and it works even when the TV is in standby. It also allows you to control TVs that do not have smart features or network connectivity.

Supported devices

The following devices have been tested with the integration:

• LG OLED55B7A

In general, LG TVs and commercial displays that expose an RS-232C control port (DE-9 connector or, on some sets, a 3.5 mm service jack) are supported.

Most LG TVs sold starting roughly 2008, as well as LG commercial signage displays, include this port. Both the modern (xb) and legacy (kb) input-selection commands are supported, so older sets work too.

Unsupported devices

• LG TVs without a physical RS-232C port. Many entry-level TVs from 2018 onwards dropped the serial port. For those, use the LG webOS Smart TV integration instead.

Prerequisites

• A physical serial connection between your TV and the system running Home Assistant. This can be a direct serial (RS-232) cable, a USB-to-serial adapter, or an ESPHome-based serial proxy.
• LG TVs use a null-modem (cross-over) cable: the TX and RX lines must be swapped.
• RS-232C Control must be enabled on the TV. On many LG models this option lives in a hidden service (InStart) menu. Consult your TV’s documentation.

Configuration

To add the LG TV via Serial device to your Home Assistant instance, use this My button:

Supported functionality

The integration adds a single media player entityAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more] for the TV.

Media player

For supported TVs, you can use Home Assistant to:

• Turn the TV on and off.
• Change the volume and step it up or down.
• Mute and unmute the TV.
• Select the input source.

Data updates

LG TVs do not report changes on their own over RS-232, so Home Assistant pollsData polling is the process of querying a device or service at regular intervals to check for updates or retrieve data. By defining a custom polling interval, you can control how frequently your system checks for new data, which can help optimize performance and reduce unnecessary network traffic. [Learn more] the TV every 5 seconds for its power state, input source, volume, and mute state. Changes made with the TV’s own remote are picked up at the next poll.

While the TV is in standby it only answers the power query. Other attributes, such as volume and input source, are populated once the TV is on.

Automation examples

The real power of this integration is tying the TV into the rest of your home.

Turn the TV off when everyone leaves home

automation:
  - alias: "Turn off the living room TV when away"
    triggers:
      - trigger: state
        entity_id: zone.home
        to: "0"
    actions:
      - action: media_player.turn_off
        target:
          entity_id: media_player.lg_tv

Switch to the HDMI input when starting movie night

automation:
  - alias: "Movie night switches the TV to HDMI 1"
    triggers:
      - trigger: state
        entity_id: input_boolean.movie_night
        to: "on"
    actions:
      - action: media_player.turn_on
        target:
          entity_id: media_player.lg_tv
      - action: media_player.select_source
        target:
          entity_id: media_player.lg_tv
        data:
          source: "HDMI 1"

Known limitations

• Many LG TVs ignore the power-on command over RS-232 while the set is in standby. If turning the TV on does not work, you might have to disable a power saving mode.
• Different LG models support different subsets of the RS-232 command set, so some input sources may not be selectable on every TV.
• If the TV is configured to route audio to an external output (such as optical or HDMI ARC) instead of the TV speakers, the volume controls are not shown for the media player.

Troubleshooting

Can’t set up the device

Symptom: “Failed to connect”

When trying to set up the integration, the form shows the message “Failed to connect”.

Description

Home Assistant could not communicate with the TV over the serial port.

Resolution

To resolve this issue, try the following steps:

1. Make sure the TV is powered on. The TV must be on for the initial connection.
2. Make sure RS-232C Control is enabled in the TV’s service menu.
3. Verify the cable is a null-modem (cross-over) cable and is fully seated. LG’s RS-232 jack is recessed, so push the plug in until it clicks.
4. Confirm the correct serial port was selected, and that no other software is using it.
5. If you use multiple daisy-chained TVs, confirm the set ID matches the one configured on the TV.

The TV becomes unavailable

If the serial connection is lost, the entity becomes unavailable and Home Assistant automatically reconnects. Check the cable and, for network serial proxies, the network connection between Home Assistant and the proxy.

Removing the integration

This integration follows standard integration removal. No extra steps are required.

To remove an integration instance from Home Assistant

1. Go to Settings > Devices & services and select the integration card.
2. From the list of devices, select the integration instance you want to remove.
3. Next to the entry, select the three dots menu. Then, select Delete.