External Sensors

External sensors give you additional temperature readings alongside your ECU data — without wiring them into the ECU itself. VETuner supports Shelly Pill, a USB-C powered Bluetooth bridge that connects up to 5 DS18B20 temperature probes.

Temperature readings appear in:

• Gauges — add a gauge to your dashboard and select the sensor channel
• Data Table — sensor channels appear automatically alongside ECU channels
• Log files — sensor values are recorded alongside ECU data during logging
• Gauge config dialogs — sensor channels are listed in the channel picker

External sensors are a VETuner Pro feature.

Requirements

• A Shelly Pill device with USB-C power
• One or more Shelly DS18B20 temperature sensors with 3.5 mm jack cable
• A computer with Bluetooth LE (Bluetooth 4.0+)
• Chrome, Edge, or another Chromium-based browser (Web Bluetooth API required)
• An active VETuner Pro subscription

Connecting the Pill

1. Power the Shelly Pill via USB-C (the Pill has no battery — it must be plugged in).
2. Plug your DS18B20 probes into the Pill's 3.5 mm jack sockets.
3. Open VETuner and go to Settings → External Sensors.
4. Click the Temperature Sensors (Pill) toggle.
5. The browser will show a Bluetooth device chooser. Select your Shelly Pill.

Once connected, VETuner probes for attached sensors and lists them in the settings panel.

Naming Sensors

Temperature sensors appear with default names based on their sensor ID (200–214). You can rename them to something meaningful:

1. In Settings → External Sensors, click the sensor name text field.
2. Type a descriptive name (e.g. Intake Air, Oil Temp, Coolant In).
3. Press Enter or click away to save.

The name is used as the channel identifier everywhere — gauge config, data table, and log files. Renaming a sensor changes the channel key, so any gauge configured with the old name will need to be re-configured.

Names are stored in your browser's local storage and persist across page reloads.

Adding Temperature Gauges

Once the Pill is connected and sensors are named, you can add them to your dashboard:

1. On the Dashboard tab, enter edit mode.
2. Tap + and choose Gauge.
3. In the channel picker, select your temperature sensor (e.g. Intake Air).
4. Configure the gauge title, units, and range as needed.
5. Save the gauge.

The gauge updates automatically as new temperature readings arrive (roughly every 1-2 seconds for 3 sensors).

How it Works

The Pill runs its own independent polling loop. Temperature values are pushed into the data pipeline as they arrive — no ECU connection required. This means you can see sensor readings on the dashboard even when you're not connected to your car.

When you ARE connected to an ECU, the Pill values are merged with ECU data automatically.

Troubleshooting

Related

• VETuner Pro — subscription details and feature list
• Configuring Gauges — setting up your dashboard
• Data Logging — recording sensor data to log files