If you are experiencing technical problems with your continuous glucose monitor (CGM), it is important to contact the company for support. 

Contact phone numbers for CGM companies: 

Libre: Abbott Libre 1800 801 478

Dexcom: AMSL Diabetes (Dexcom) 1300 851 056

Medtronic: Medtronic Diabetes 1800 777 808

Some tips that may be helpful with troubleshooting issues with your CGM

1. Sensor Placement and Adhesion

• Ensure the sensor is properly placed on the skin, following the manufacturer’s guidelines.
• Check if the sensor is properly adhered to the skin and not coming loose.
• Avoid areas of excessive sweating, rubbing, or high friction, as this can affect sensor adhesion and readings.
• Be mindful of any changes in skin condition, such as scarring or tattooed areas, which may interfere with sensor readings.

2. Sensor Error Messages

• Look for any sensor error messages or alerts on the CGM device or associated app.
• Common error messages include "Sensor Failure," "Sensor Warm-up," or "Calibration Error."
• Refer to the manufacturer’s troubleshooting guide to identify specific error codes and resolutions. Or contact the manufacturer for assistance.

3. Sensor Warm-up Time

• Ensure the sensor has completed its warm-up period (typically 2 hours), as readings during this time can be unreliable.

4. Interference from External Factors

• Check for possible interference from electromagnetic sources (e.g., mobile phones, microwaves, or other electronic devices).
• Ensure that the sensor is within range of the receiver or mobile device. Usually 5-6 meters.

5. Skin Conditions

• Inspect the area where the sensor is applied for any skin irritation, redness, or swelling, which could interfere with the sensor’s function.
• In some cases, sensors may not perform well on certain skin types or if there’s any infection or inflammation at the site.
  

Tips to try if you are experiencing problems with the adhesives for your CGM. There is information on adhesives, overtapes and tips for applying/removing your CGM. 

6. Battery and Power Issues

• Check if the device has sufficient battery life, especially for both the sensor and receiver (or smartphone app).
• Low battery power can affect data transmission and sensor performance.
• If the CGM uses a rechargeable device, ensure it's fully charged and connected correctly.

7. Accuracy of Readings

• Compare CGM readings with a blood glucose meter, especially if readings seem off or if there are large discrepancies.
• CGM readings may lag behind actual blood glucose levels (BGL), particularly with rapid blood sugar fluctuations.
• Check a BGL when the sensor is reading less than 4 mmol/L or 15 mmol/L or higher. 

8. Device Software/Updates

• Ensure the CGM device's software or app is up to date, as outdated software can cause malfunctions.
• Look for any available firmware updates and follow the instructions for installation.

9. Sensor Lifespan

• Check if the sensor is still within its recommended usage time. Most CGMs have a lifespan (e.g., 7-14 days) after which they need to be replaced.
• Ensure that the sensor has not reached its expiry date, as this can lead to inaccurate or erratic readings.

10. Environmental Conditions

• Ensure the sensor is not exposed to extreme temperatures, humidity, or direct sunlight for prolonged periods.
• Avoid using the CGM in environments with high moisture (e.g., swimming, sauna, or heavy sweating) unless the device is rated for water resistance.

11. Device Compatibility

• Verify that the CGM system is compatible with the receiver, smartphone app, or insulin pumps that you're using.
• Confirm that any other connected devices are properly synced with the CGM to ensure accurate data transmission.

12. User Error

• Ensure that the device is being used according to instructions, especially with regard to sensor insertion and placement.
• Review the setup process to make sure all steps were followed carefully, as improper installation can cause malfunctions.

**These troubleshooting steps should cover the common issues that can arise with CGM devices.

Depending on the specific brand and model of the CGM, you may also want to refer to the user manual or the manufacturer's troubleshooting guide or contact manufacturer directly for additional support.

Page updated November 2024