How you recognise it
After replacing a faulty external sensor (temperature + humidity, CO2, or other EXT sensor), the new sensor still doesn’t communicate with the IO module. The sensor shows no values or remains in an error state.
Cause
There are three common causes:
- Module cache - The IO module remembers the old sensor and doesn’t automatically detect the new one
- Power cycle needed - The module needs a restart to reinitialize the sensor port
- Upside down connection - The sensor connector is plugged in upside down (the connector has no locking mechanism to prevent incorrect orientation)
Solution
Step 1: Find new devices
Service installation partner
- Go to Settings → Hardware
- Select the IO module where the sensor is connected
- Run Find new devices
- The module will scan for and register the new sensor
Step 2: Power Cycle the Module
Service installation partner
If Find new devices doesn’t help:
- Disconnect power from the IO module
- Wait 10 seconds
- Reconnect power
- The module will reinitialize and detect the new sensor
Step 3: Check Connector Orientation
Service installation partner
If the sensor still doesn’t work:
- Unplug the sensor connector from the EXT port
- Try plugging it in upside down (rotated 180°)
- The connector has no locking mechanism, so it can be inserted incorrectly