Dexcom G6 glitch: transmitter battery critically low, and then dies (with no other warnings)

Has this happened to anyone else? It’s happened to me twice in a row, now. This time, I didn’t have a backup ready to go.

I don’t use the receiver- only the Android phone app.

This is the second time in a row I’ve not gotten any low transmitter battery warnings until it was too late. I received the critically low warning- and then the transmitter died within an hour or two, leaving me no time to get a new one. (The transmitter is still under warranty for another ten days).

I called tech support on Thursday, and asked for them to overnight me a new transmitter, hoping to get one before the holiday. It never arrived (I only received an email saying they were fulfilling my order).

Overall I love my G6 but Dexcom is not without it’s failures. I was one of the people who repeatedly received defective G4 receivers (the speaker died, leaving me without any audible alerts). It happened repeatedly-- I had to exchange 3 or 4 of them-- all the while, tech support never acknowledged this was a widespread issue. When the recall happened, of course then everyone acknowledged it. But when it was happening, I felt like the company was gaslighting me. It was very disconcerting.

I am left wondering now whether the Android software has a known issue with not sending out battery alerts, and the reps just aren’t acknowledging it.

Has anyone here experienced this problem? The tech support rep suggested I use the receiver, which should yield more reliable results.

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I use an Android phone and haven’t had this issue. What are the first 2 digits of your failed transmitters? I just started an 8K but my previous transmitters were older versions. I have heard of this issue but kind of rarely. It pops up every once in a while on Tu-diabetes. Did this happen in the last week or two of your transmitters expected life on both transmitters?

My insurance gives me two transmitters at a time so I don’t run into being without a transmitter if there were to be a failure. I am really lucky with Dexcom G6 though, I’ve only had one sensor that needed replacing and no transmitter problems in over a year of use.

I just started on the G6 almost ten days ago and am using my first sensor and transmitter. Your experience is troublesome, especially happening with two transmitters in a row.

I did a “Dexcom G6 transmitter sudden death” google search and found this recent reddit thread.

So you’re not alone, but that doesn’t help your situation.

I’d also be interested in knowing your transmitter serial number first two digits of both of the failed transmitters.

Are your blood glucose levels relatively stable or are they more variable? If you don’t mind, could you share your standard deviation number that’s in the Dexcom reports?

I’d also be curious if using the Dexcom receiver instead of the Android phone might alleviate this transmitter early and sudden death syndrome. Do you have a Dex receiver?

Do you have a back-up fingerstick meter and a supply of strips? If this happened to me, I would seriously consider using some limited fasting and increased finger-stick regimen to manage my glucose until the replacement transmitter arrived.

I will be interested to read how this situation resolves for you! Good luck.


I don’t know the earlier one, but the current failed transmitter serial no. starts with 8G.

My insurance gives me 2 at a time as well, though that leaves very little room for error. And as I’ve documented, even their “overnight” service takes several days to process. I’ll probably end up getting my regular reorder from Byram Healthcare around the same time as my “expedited” Dexcom emergency shipment.

Hi Terry, as stated in my reply to Firenza, my current (failed) transmitter starts with 8G. I don’t remember the prior one (is there a way to look it up?) I do have a receiver. The alerts are a lot more invasive than the phone, so I’ve stopped using it. In particular, at night when my BG floats around my high (180 mg/dl) mark, it will go off repeatedly. (e.g. 178, 182 ALARM, 179, 177, 181 ALARM… etc.) Dexcom really needs to address this issue.

Thankfully I did just order a bunch of test strips. Since switching to G6 I’d been subsisting on one bottle of 50 that’s lasted me for months, but a few weeks ago I decided it wouldn’t hurt to have more in supply. I’m glad I did.

My standard deviation is 47 mg/dl (is that good? That’s new data for me, and I’m not sure how to interpret it.) GMI of 7.2%. Not great, but not terrible either. I’m really looking to closed loop tech to help me really dial in my numbers.

I hate when that happens! It’s as if the system knows how to irritate you best. Alarm fatigue is a real factor that we need to manage. When that happens to me, I will set a higher alarm for the rest of the night to get above triggering the alarm.

I have a theory about higher BG variability using up the transmitter battery more quickly that lower variability. I have no evidence that it’s true but I’m thinking that higher variability uses more power of the transmitter battery than lower variability.

I’m aware of some algorithms that only update when the parameter has changed, so when you enjoy relatively flat glucose over time, the transmitter battery does not have to update the receiver as often. Again, this is just my way of thinking about it and I have no specific knowledge of these systems.

A standard deviation of 47 mg/dL means that about 2/3 of your glucose data falls within +/- 47 mg/dL of your glucose average, a 94 mg/dL window. That’s a fairly wide window and implies a good deal of up and down movement. In any case, if you were able to reduce your standard deviation from 47 mg/dL to say, 40 mg/dL, you may put less strain on the transmitter battery and feel better as well.

I hope you can get your transmitter replaced soon.

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I had same with my mail order dme provider, but this leads to possible early death of 2nd trans.
I recently switched to getting transmitter one at a time, via pharmacy, so quick access to get when ready for new one.

There are 2 ways transmitter ends. It hits day 112, or battery is too low. Low battery may be more likely on 2nd trans when get 2 at a time. Dexcom will cover replacement under some circumstances.

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@Terry4 I just had this sort of happen. It has nothing to do with higher numbers though because I don’t often have higher numbers at all. I stay 99% under 160 and 96% under 140. (low is set at 65) My A1C is 5.1%. My sensor number starts with 8G.

But I use the reader and phone and I got a low battery alert at around 80 days. Plus my reader kept losing connection. Abnormal unless my sensor is on it’s last legs for me. I called them because I remembered some kind of warning but thought it came at a later period or a different message?? They told me no, it was meant to last only 90 days and that is the normal alert. Pure Bs, but it was still working sooooo. My phone had no issues at that time.

But at 87 days my phone lost connection, first for about a half hour, but then a couple of hours after I was asleep for the whole night it turns out. My reader worked though. But I called and they said they would send a replacement out for a sensor and a transmitter. I realize it was on day 87, but I had called earlier, plus I was aggravated about the first call being ignored.

Last year I had a transmitter that wouldn’t stay in the holder well and had called and they said they would overnight one to me. I got it a week later. But the day after I called I managed to get it to stay so at least I had it working until the replacement arrived. But that made me realize how vulnerable I was to having a ton of back up for sensors, but not for the transmitter? So I had my doctor call in a script to Costco and bought an extra one I keep in rotation but that way I always have an extra. They are $149 at Costco not using insurance, so for me it was worth it.

@MM1 you have a point of the possible 2nd one because it gets closer to the expiration date. But I have had the extra one in rotation for over a year now and this is the first time it has happened. But it’s possible that is one of the causes. I still want my back up though!!!

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I just had 2 G6 transmitters in a row fail. First one ended the session after a month and there was no restarting it, nothing. Dexcom sent another one and it was defective from day 1. Never had any problems at all in 2 years and now this. I think their quality control is really taking a dive.

My G6 transmitter failed after exactly 30 days, as a result of rapid battery failure. I also have no backup, so I have no CGM until a replacement (hopefully) arrives in a few days.
I use only the Dexcom receiver, which is a reprogrammed G5 receiver. It showed the “Battery Critically Low” warning one day before total failure.