If You See the Message "No Sensor Detected" Reported by Your Sensor

When a sensor reports No Sensor Detected

Some sensors report the error, “No Sensor Detected” when the sensor is not able to retrieve a reading from the sensor probe. There are a few sensor types such as Temperature, Humidity, or Thermocouple which might exhibit this error. This error is generally a result of damage to a sensor with a wired probe (though it can also occur with a standard sensor that does not have a wired probe). To diagnose this, see the steps below.

  1. If the sensor has a wired probe, examine the wire for kinks, nicks, cuts, burns, or if it has been severed.
  2. Be sure the probe wire is not run through a door, window, or other placement which might pinch the wire.
  3. If the sensor is a Coincell or AA form factor, remove the cover and batteries and examine for a secure connection where the probe wire connects to the sensor body.
  4. With the batteries removed, examine the sensor circuitry for signs of liquid ingress or corrosion.
  5. Visually examine the sensor’s circuitry for weak or damaged solder points.

Data values associated with this error

A sensor with this error will provide the following error, which our software associates with the No Sensor Detected error.
Temperature reading: -999.9°C
Sensor State: 34

Troubleshooting

After examining the probe for damage or a loose connection, execute the following steps.

  • Remove the sensor from any freezer/fridge in which it might be operating
  • Be sure the sensor is being tested with the probe wire straight and not pinched or kinked
  • Reset the sensor to the default settings using the gray Default button under the Settings tab of the sensor (it will accept default configurations on the next Heartbeat)
  • Remove the batteries for 60 seconds
  • Insert known-good batteries
  • Watch for the sensor to report No Sensor Detected

If the issue persists, the sensor will likely need to be returned for repair. If the probe wire is damaged, the cost for this repair is not covered under the warranty and is generally US $30 or less.