What does the Sensor Error alert mean?

If you are experiencing a Sensor Error alert and are not getting Dexcom G6 readings, it means the sensor is temporarily unable to measure the glucose OR your components are not communicating. Tap the alert to get more information. You may also view our guide on troubleshooting sensor errors.
Please note you will not receive glucose alarm/alerts or Dexcom G6 readings until fixed. Use your meter for treatment decisions.
Possible reasons of sensor error include:
  • Previous sensor session wasn’t ended and the transmitter still trying to connect to old sensor.
  • Sensor site bleeding during insertion
  • Incorrect transmitter SN entered in the display device.
  • Transmitter is beyond 90-day activation period.
  • Transmitter isn’t snapped in correctly. Transmitter tab isn’t seated under the plastic lip in the slot.
Wait up to 3 hours while the system fixes itself. If not corrected after 3 hours, you’ll see a screen that says, "Sensor Failed". Contact Technical Support (available 24/7) by submitting a request below or call 1-844-607-8398.
For more information on sensor errors, read the Dexcom G6 User Guide.

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