Is this what a slowly failing sensor looks like?

I’ve been extending my sensor beyond 10 days, but at some point it starts to fail. I was getting the following patterns and wondered if this is the kind of data that comes from a slowly failing sensor:

See those drops every 6 or 7 readings?


That’s very similar to my sensor failures but they occur beginning day 7 getting worse each day to 10 if I don’t change it sooner.


Yes that is the pattern I’ve seen many times a day or so before the end. That pattern also occurs if the sensor tape is getting loose. Lately I’ve had sensors that go 12-14 days with a restart. Seems to vary by lot.

Yes, also looks like compression lows, but more likely a failing sensor.


fyi - I have kept that same sensor and it still seems to be working … so it can take a long time to fail.



Having a similar experience with my current transmitter on a G6. It’s not terrible, but has a habit of suddenly showing a drop into low territory (60-70) at 4:30 to 6:30am and setting off one or two alarms with the Dexcom app and/or Sugarmate….one look at a graph and I know its an anomally…like a compression low with no compression…very irritating for those of us with experience enough to recognize it, very disconcerting to those of use that don’t…

So my question is: The transmitter should last another 4 days, but I’m really tired of getting woken up in the early am…it’s like it’s playing a game with me to see how long I’ll take it. So, do I report it and ask them to send me another one or do I put up with it for another few days and replace it with the one that just arrive yesterday in my next order? Part of me wants to say “Hey, you own me…” and part of me wants to play the good patient and deal with it… I must be getting it used to this stuff to have these conflicting viewpoints….

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We pay a lot for these things. If it doesn’t’ make it the full 90 days, I will report it.

If it is on day 91, I won’t.

Just my personal policy on it.

This has nothing to do with the transmitter, the drop are tissue or compression issues. It could also be the location of the sensor wire.

These are compression lows.

I respectfully think you’re wrong. I’ve had compression lows, in fact I’ve used them as a snooze alarm by rolling on the sensor. Never not once cause a loss of data.

These happen around day 7. The pattern is usually the same. BG is fairly steady with a sudden drop over 15 minutes. Often this results in a loss of signal from the transmitter with a message to no change the sensor, wait up to 3 hours.

When it starts it gets progressively worse over time. It can happen while walking, standing or sleeping; wit a new or old transmitter. I’ve read some G7 people are having the same issue.


FWIW until this morning I never had a compression low with either the G6 or the G7, but then I didn’t wear the G6 on my arm. This morning it happened to me:


The lows correspond to me shifting to lie on my RHS; the (G7) sensor is on my right upper arm (about 11 o’clock if the back is 12). I stopped sleeping on my RHS some time after 2:30 AM, the red-dot-in-a-square at 4AM is when I did a fingerstick to make sure my suspicions were correct. The shot of the G7 is from a few minutes ago. This is the first time I have observed bleeding on a G7 (this is G7 number 10 for me).

All the previously posted “dropouts” as I call them are failing sensors, not compression lows. The G7 is a lot better for failures (I’ve seen a few but not as many as with the G6). Battery voltage on this G7 is 249cV (load) and 288cV (no load), but as the fingerstick shows it is doing fine against a Contour Next One test strip.

The chart posted has no missing data.

It doesn’t always lose data.Compression lows don’t just start at 7+ days in with none for the first 6 days on multiple sensors. I had a good string of 5 sensors with no issued, not so with number 6 got erratic on day 7 and really stupid through to day 10. I stuck with it out of stubbornness, turning C-IQ off and my phone so I could get some sleep. On and a lot of finger sticks before bolusing for meals.

Apparently this isn’t my week! Just finished breakfast when the high pitched scream of my Dash pod broke the quiet! Haven’t broken the code on the problem with the Dex G6 issue yet, planned on replacing the sensor today, possibly the transmitter as well (just got my next 90 day supply from WELLSTART) with replacement sensor from Dexcom for the problem child one (Dexcom tech support [second level] wouldn’t listen to the logic that the sensor can’t tell time so it doesn’t know to malfunction between 1am and 7am consistently…yet it does!). Last night was particularly wonderful: Was woken up no less than 6 times for lows that didn’t exist. If in doubt, rip it out, here I come….didn’t have the energy last night. So now the Dash pod with 50+ units decides it doesn’t like to communicate either! Makes me wonder if my phone might be the problem! Time and new equipment (G6 sensor and Dash pod) will give a better picture. I so like tracking intermittent things like this down in electrical equipment…not! Se la, I’m above ground and able to walk around, eh? If only I can convince myself of that!


I like this even better than “when in doubt, change it out!” I guess the mood when changing out the sensor, transmitter or pump would drive, and dictate, which of the two above you do. Lol

Sorry you are having these issues but thankfully Dexcom replaces the tech without issue.


I’ve had similar problems - often with sensors I’ve newly installed. So these days I will not install sensors in the evening as if I have problems it’s in the first 12 hours or so. I’d rather have these problems (the insistent lows and warnings) during the day.

For Dexcom, It seems like as the technology gets older, the problems become more troublesome. Maybe it’s a supplier issue?


I tried the Dexcom form first, but got an error and was told to call in. The first 3 people spoken with demonstrated little knowledge of the product and all three insisted the sensor was the problem despite the short window of time each night the problem was limited to (early morning 1-7) and the sensor has no time awareness. Based on my submission and rating, a Dexcom tech called me back just now. The disturbing part: she’d thought nothing of having called me and then asking me to verify my name, DOB, and address…She was taken aback when I said “No! You can’t call someone and ask them for the exact information any scammer would like to have.” Next, “If there’s something you can tell me that I know to confirm you are who you say, then we can talk…” she finally came up with the case number Dexcom had assigned. (What’s up with companies that don’t get this is a terrible approach!) She seemed very knowledgeable. We discussed calibrating (I know there’s lots of opinion on this) and said do calibration should do and seemed shocked when I told her it takes everyone I know to two at a time to get G6 and finger stick in sync. She said do one, wait 15 min, do another if needed, wait 15 min, do a final and if it isn’t in-synch with a finger stick, Dexcom will replace it without question…I advised her she’s the first tech that’s ever said anything about “without question” and normally it’s fight if one calls in, so I usually use the form. She at least understood my point about the sensor not having time awareness and admitted she had no explanation as to why it would err in the am period.

Next call went to Insulet about my “screamer” this morning. Has anyone broken the code on how not to stay on the phone for 30+ minutes with numerous inane questions with Insulet? The lady was nice, but seemed brand new, unsure of herself. Luckily, I’ve only had to call them twice, one about 18 months ago and today (in the grand scheme not bad!), but both times the people haven’t seemed “familiar” with what they need to ask and both had to keep going to “talk with the manager” like I’m buying a car. Not a good feeling, and both times I had to ask whether a replacement would be sent. Is Insulet just that stingy or am I just lucky? (BTW, yes, they’re sending a replacement!).

We’ll see how the new G6 sensor and pod work out…if its another 18 most, I’ll count myself lucky!


Sorry, this is hilarious! LOL… Seriously, I’m glad they are replacing the pod. I also rarely have had to call Insulet, at least not in the last 4+ years when I experienced multiple failures for a few weeks straight. I don’t know why they occurred, but I also had just started Loop on iOS (and no longer using the PDM), and simultaneously I had switched from G5 to G6. Maybe it was a bad box of pods. They did replace each pod that I called in at that time without issues. Maybe Insulet has gotten more stringent in recent years.


I apologize if this seems drawn out…but…I just got yet another call from a Dexcom Tech Support gentleman. He said he’s been T1 for 17 years, using the product, asked where I put my sensor, told him my upper arm, and he said, “ahhh, you see that’s the problem, its not made for the arm, it will only work accurately on the stomach.” As he’s saying this, I did a web search for “where to put the Dexcom G6 sensor.” The first entry, a Dexcom website, reads: “Dexcom G6 sensors may be inserted **on the abdomen, the back of the upper arm, or on the upper buttocks.” Now, there are a couple caveats, but the video below the quote shows an adult women inserting the sensor on their upper-left arm! I’ll grant she’s nicer looking than me, but… The gentleman’s response, “I’ll have to talk with the website people about this error!” He said he’d have another “software expert” give me a call and explain why I’m wrong and the sensor can tell time… I’ll be waiting for the call…


Wow, incredible! This has got to be really frustrating! I also wear my sensor on my upper arm. In fact, the sensor failed when wearing it on my abdomen. I think @JessicaD suggested I try my arm and that worked!