Signal loss
Also called lost signal, no data, no readings.
Signal loss is when the phone or receiver stops getting values from the CGM sensor. On a Dexcom G7 the last value stays on screen for 10.5 minutes, then the display shows a dash and a Signal Loss alert. Common causes are distance, a wall or water between sensor and phone, and phone battery settings. (Dexcom)
Worked example
A G7 value of 112 mg/dL (6.2 mmol/L) arrives at 1:00 a.m. and nothing follows. At 1:10:30 the screen shows a dash, then Signal Loss. Dexcom asks people to contact technical support if it lasts more than 30 minutes.
Related terms
Sources, quoted
- Dexcom: “The Signal Loss Alert occurs when your display device* temporarily stops getting glucose readings from your Dexcom G7 sensor.”
- Dexcom: “Your last sensor reading will show on your display device for 10.5 minutes, if a new reading does not come in after that time, your display goes to —, indicating that there has not been a reading.”
- Dexcom: “Your display device may be too far from your sensor or there may be something, such as a wall or water, interfering with your sensor and your display device.”
- Dexcom: “If Signal Loss continues for more than 30 minutes, contact technical support.”
- Dexcom: “can also cause Signal Loss.”
Every quote above is checked against its source page before each update of this site; last checked 2026-10-06. The worked example is our own arithmetic. This page explains a term; it is not advice for a person's treatment.