add Data Grand Lyon documentation

source/_integrations/data_grand_lyon.markdown

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+---
+title: Data Grand Lyon
+description: Instructions on how to integrate Grand Lyon open data into Home Assistant.
+ha_release: 2026.6
+ha_category:
+  - Sensor
+  - Transport
+ha_iot_class: Cloud Polling
+ha_codeowners:
+  - '@Crocmagnon'
+ha_domain: data_grand_lyon
+ha_config_flow: true
+ha_platforms:
+  - sensor
+ha_integration_type: service
+ha_quality_scale: bronze
+---
+
+The **Data Grand Lyon** {% term integration %} lets you monitor data from the [Grand Lyon open data platform](https://data.grandlyon.com/) (city of Lyon, France).
+
+With this integration, you can track upcoming departure times at transit stops.
+
+## Prerequisites
+
+This integration uses data from the [Grand Lyon open data platform](https://data.grandlyon.com/).
+
+You need an account on [data.grandlyon.com](https://data.grandlyon.com/). Sign up for a free account if you don't have one. Then, request access to the [dataset](https://data.grandlyon.com/portail/fr/jeux-de-donnees/prochains-passages-reseau-transports-commun-lyonnais-rhonexpress-disponibilites-temps-reel/info). You can find more information about how to properly create an account and set a password [here](https://rdata-grandlyon.readthedocs.io/fr/latest/authentification.html) (fr).
+
+You also need to know the stop IDs you want to monitor. You can find these on the [Grand Lyon data portal](https://data.grandlyon.com/).
+
+{% include integrations/config_flow.md %}
+
+{% configuration_basic %}
+Username:
+  description: "Your username on data.grandlyon.com."
+Password:
+  description: "Your password on data.grandlyon.com."
+{% endconfiguration_basic %}
+
+After setting up the integration, you can add transit stops as sub-entries from the integration's configuration page.
+
+### Adding a transit stop
+
+1. Go to {% my integrations title="**Settings** > **Devices & services**" %} and select the **Data Grand Lyon** integration.
+2. Select **Add transit stop**.
+3. Enter the following information:
+
+{% configuration_basic %}
+Line:
+  description: "The transit line identifier (for example, `C1` or `T2`)."
+Stop ID:
+  description: "The stop identifier. You can find the stop identifier on the [Grand Lyon open data platform](https://data.grandlyon.com/portail/fr/jeux-de-donnees/prochains-passages-reseau-transports-commun-lyonnais-rhonexpress-disponibilites-temps-reel/info). Zoom on the map and click on a stop. The ID will be displayed on the panel on the right, at the bottom. The field is called `id`."
+{% endconfiguration_basic %}
+
+## Supported functionality
+
+### Entities
+
+The **Data Grand Lyon** integration provides the following entities.
+
+#### Transit stop sensors
+
+For each transit stop you add, the following sensor entities are created:
+
+- **Next departure 1**
+  - **Description**: The departure time of the next vehicle at this stop.
+
+- **Next departure 1 direction**
+  - **Description**: The direction (destination) of the next vehicle at this stop.
+
+- **Next departure 1 type**
+  - **Description**: Whether the departure time is _estimated_ (based on real-time vehicle tracking) or _theoretical_ (based on the scheduled timetable).
+
+- **Next departure 2**
+  - **Description**: The departure time of the second vehicle at this stop.
+
+- **Next departure 2 direction**
+  - **Description**: The direction (destination) of the second vehicle at this stop.  Disabled by default.
+
+- **Next departure 2 type**
+  - **Description**: Whether the departure time is _estimated_ or _theoretical_. Disabled by default.
+
+- **Next departure 3**
+  - **Description**: The departure time of the third vehicle at this stop.
+
+- **Next departure 3 direction**
+  - **Description**: The direction (destination) of the third vehicle at this stop. Disabled by default.
+
+- **Next departure 3 type**
+  - **Description**: Whether the departure time is _estimated_ or _theoretical_. Disabled by default.
+
+## Data updates
+
+The integration polls data from the Data Grand Lyon API every 5 minutes by default.
+
+## Known limitations
+
+- The integration provides up to three upcoming departures per stop. If fewer departures are available, the remaining sensors show as unavailable.
+- There is no estimated data for subways, only theoretical.
+
+## Troubleshooting
+
+### Can't set up the integration
+
+#### Symptom: "Invalid authentication"
+
+When trying to set up the integration, the form shows the message "Invalid authentication".
+
+##### Description
+
+This means the username or password you entered is incorrect.
+
+##### Resolution
+
+To resolve this issue, try the following steps:
+
+1. Make sure you are using your [data.grandlyon.com](https://data.grandlyon.com/) credentials.
+2. Log in to the Grand Lyon data portal directly to verify your credentials work.
+3. If you forgot your password, reset it on the Grand Lyon data portal.
+
+### Transit stop shows no data
+
+Make sure the line identifier and stop ID are correct. You can verify these on the [Grand Lyon open data platform](https://data.grandlyon.com/portail/fr/jeux-de-donnees/prochains-passages-reseau-transports-commun-lyonnais-rhonexpress-disponibilites-temps-reel/info).
+
+## Removing the integration
+
+This integration follows standard integration removal.
+
+{% include integrations/remove_device_service.md %}