Dexcom G7 - My sensor failed!
This page is not giving you medical advice or treatment advice, and that is very much on purpose! I am not a medical professional, and even if I were, I don’t know your personal circumstances. If you need medical advice, consult your physician! If, at any time, you have reason to doubt your G7 readings, use one or more finger-stick measurements to confirm your G7 readings. Base your treatment decisions (bolus, etc.) on the finger stick reading, and in accordance with your physician’s instructions.
For users with an insulin pump controlled by the G7: Until you have reached a full understanding of your G7’s behavior and when, in your particular case, its readings can be trusted, you may need to double-check, as frequently as necessary to give you confidence, with finger stick readings. Read the page on reading comparisons for important information on interpreting the differences.
Pages
- Introduction
- How it works
- Accuracy and Calibration
- Comparison with finger stick readings
- My Sensor Failed
- Known Issues
- Contacting Dexcom
Dexcom G7 - My sensor failed!
Information you will always need when contacting Dexcom for a replacement: Sensor serial number, Lot Number, and Insertion Date. It is best to record these (photos?) as you insert the new sensor. Alternatively, you can retain the box and applicator until after the sensor’s regular lifespan.
When your sensor fails to provide readings, produces readings that seem consistently wrong, produces constant low or high values, etc., you have a problem. Your problem is that you cannot manage your diabetes effectively, so what are you to do? One seemingly obvious answer is to rip off the failing sensor, install a new one, and hope it works. You figure you can apply for a replacement after you rectify the situation. You may be wrong…
Please follow the flowchart below. If you get to an instruction to contact customer service, proceed to the flowchart for that process. Otherwise, you may arrive at the after pairing flowchart.
The way I have structured things, instructions for installing a new sensor appear at the end of the customer service contact procedure.
The flowcharts will not render properly if JavaScript is disabled!
The reason for using flowcharts is that they are easier to follow than a lengthy text. They are not official Dexcom communications, have been compiled by me, and are not guaranteed to be correct or to cover all possible cases!
---
config:
theme: redux
---
flowchart TD
Start(["Start"]) --> When
CSCall[["`<a href='/blog/pages/dexcom/g7-contacting-dexcom/'>Contact Customer Service Flowchart</a>`"]]
End(["Continue"])
When{"When?"}
When -- During Insertion --> Insertion
When -- During Pairing --> Pairing
When -- After Pairing --> AfterFlowChart
Insertion{"Issue?"}
Insertion -- Other --> CSCall
Insertion -- Filament/Needle Alignment --> Alignment
Insertion -- Bleeding --> Bleeding
Alignment["Take photo, do not insert"] --> CSCall
Bleeding("Leave sensor alone,<br>gently clean blood,<br>it may well work,<br>proceed with pairing")
Bleeding --> W24H@{ shape: delay, label: "Wait until 24 hour mark, or<br>Failure message"} --> End
AfterFlowChart[["<a href='#after_pairing_flowchart'>After Pairing Flowchart</a>"]]
Pairing{"Tapped<br>"Replace Sensor", or<br>"Pair New Device"?"}
Pairing -- Yes --> Code
Pairing -- No --> TapReplace["Tap "Replace Sensor""] --> End
Code{"Confirmed pairing?"}
Code -- No --> BTOff
Code -- Yes --> Warmup
BTOff("Switch Bluetooth Off") --> RemoveAll
RemoveAll("Forget all Bluetooth entries<br>name starting "DXC"") --> Wait1Min
Wait1Min@{ shape: delay, label: "Wait one minute" } --> BTOn
BTOn("Switch Bluetooth On") --> End
Warmup@{ shape: delay, label: "Warmup Starts:<br>Wait 30 min"} --> End
Please find more information about bleeding on the known issues page.
After pairing troubleshooting steps
If your trouble develops after the initial pairing and warm-up, please follow the flowchart below.
---
config:
theme: redux
---
flowchart TD
Start(["Start"]) --> What
CSCall@{ shape: f-circ, label: "Junction" } --> CSCall1 ~~~ TwentyFour
CSCall1[["`<a href='/blog/pages/dexcom/g7-contacting-dexcom/'>Contact Customer Service</a>`"]]
What{"What happened?"}
What -- "Gaps in Readings" --> Phone
What -- "Abnormal Readings" --> MustConfirm
What -- "Sensor came off, or<br>"Sensor Failed", or<br>"Replace Sensor"" --> CSCall
What -- "Wild fluctuations in Readings" --> Fluctuations
What -- "Readings stopped" --> LifeSpan
Phone["Bring phone closer"] --> W15
MustConfirm{"Perform finger stick measurement.<br>Result?"}
MustConfirm -- "Extremely Low/High" --> LowHigh
MustConfirm -- "<a href='/blog/pages/dexcom/g7-reading-comparison/'>Within Spec</a>`" --> NormalEnd
LowHigh{"Low or High?"}
LowHigh -- Too Low --> Lows
LowHigh -- Too High --> CSCall
Lows{"Possible cause?"}
Lows -- Sleeping --> PL
Lows -- Wearing Tight Clothes --> CL
Lows -- Other --> CSCall
PL["Pressure low<br>Change sleep position"] --> W15
CL["Pressure low<br>Change clothing"] --> W15
Fluctuations{"During the first 24h?"}
Fluctuations -- No --> CSCall
Fluctuations -- Yes --> TwentyFour
W15@{ shape: delay, label: "Wait 15 min"} --> CheckAgain
LifeSpan{"Have you used up the lifespan plus grace period?"}
LifeSpan -- No --> CSCall
LifeSpan -- Yes --> NormalNew
NormalEnd(["This is normal!"])
NormalNew["This is normal!"] --> NS
NS(["Replace Sensor:<br>Save Information"])
TwentyFour@{ shape: delay, label: "This may be normal,<br>wait until 24h"} --> CheckAgain
CheckAgain(["Check Again"])