How often have you gotten ? ? ? on Dexcom G5?

How often have you gotten ??? and how often has it resolved itself.

Also, how often does your receiver miss a reading (no backfill on G5 receiver)?

My first day, I had 4 missed data points.

Yesterday, I got my first “???” for about 15 minutes, got some accurate numbers for a short time, and then permanent “???”.

Sensor wasn’t loose, and had given very accurate readings for many days prior to the ???

I use a G4 but I’ve noticed a definite positive correlation between showering and the appearance of the ??? display. It doesn’t happen every time I shower but when the ??? does appear it’s often shortly after a shower.

My last sensor had entered a third week of service and after my shower I saw the ??? alert. I decided it was time to change my sensor anyway so I peeled away the entire bandage/sensor pod/transmitter assembly and carefully released the transmitter from the sensor pod. I noticed that the underside of the sensor and the top side of the sensor pod both had small water drops.

I have had ??? situations in the past when I’ve dismounted the transmitter and thoroughly dried the pod and the transmitter and snapped it back in. This has often cured the ??? for me.

Now I’m not saying that every ??? display is caused by water intrusion under the transmitter; there are other reasons to cause this display.

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Thanks for that info, Terry. I was wondering if water is the issue. However, this happened while I was sitting for some time. I have showered at least 8 times w/o incident. I have sweated a lot during hikes. But I am concerned about the seemly “iffy” connection between the sensor and the xmitter.

If you are familiar with MM sensors such as Enlites, you know that there are orings to prevent moisture from working it’s way into the connection socket. Hence, I was surprised (not in a good way) to see that Dexcom opted for, what appears to my unknowledgeable eye, to be a flat, problematic interface between the terminals on the sensor and those of the xmitter.

The Dexcom sensor pod/transmitter connection is interesting. The bottom of the transmitter has two small circular electronic connections points that mate with two black rubber “donuts” on the sensor pod. This rubber must be electrically conductive yet it’s also designed to keep out moisture, at least most of the time.

I have also found bad readings due to the transmitter not fully engaging both release tabs of the sensor pod. Here’s a few pictures for reference.

49 PM

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The dreaded ??? has, unfortunately, nothing to do with the Riddler. I get it at two distinct times: when my transmitter gets waterlogged and when I have a bad sensor. I rarely get waterlogged anymore because I have stopped showering. :wink:

I haven’t had many bad sensors, so it really doesn’t happen that often. But when a sensor is bad, it’s bad…and it needs to be replaced. Always complain to Dexcom: they are good about replacing funky sensors.


LOL! Reference understood! :):grin:

I get ??? all the time. So annoying. I love my Dexcom and would sooner give up my pump than it, but I have the hardest time keeping it on despite using medical tape and giff grips (which are the best IMHO) and this glue stuff someone here recommended (can’t recall the brand name). I never can make one last more than a couple extra days beyond the one week period.

For reference, I exercise daily and shower daily. And I too get the ??? often after a shower.

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Have you ever tried to remove your transmitter from the sensor pod so that you can dry both mating surfaces? It’s a little tricky and something that Dexcom likely frowns upon. You may use the safety lock tool depicted above or some people can do this with their fingernails.

The best way to get a feel for how this works is to practice when you remove the whole assembly and can place it on well-lit table in front of you. I use kleenex and sometimes a hair-dryer on the low heat setting to dry the mating surfaces.

@Terry4 I actually have done that once only by way of error…I needed the serial number on the transmitter, but didn’t want to put in a new site! It was very hard to get it out LOL So when you do this, do you then have to wait 2 hours to re-calibrate? I don’t know, since when I did it I was calibrating a new site.

No. Your system will miss any five-minute data points for the duration of your transmitter removal, but I can usually do this in less than five minutes. When you click the transmitter back in your session resumes as if nothing happened, except hopefully the darned ??? disappear. Practicing this with an bandage/sensor pod/transmitter assembly off of your body helps a lot to learn how to do this.

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I use my cell phone to take pictures of all sorts of things for reference. As soon as I received the G5 system, I took a pic of the bottom of the xmitter (for the serial number). Because Google Photos can find a photo from among the many I have on my account (which means they are all available on my phone), I can find things by doing a search (you can’t do that with the Gallery app-search there is next to useless)

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The transmitter serial number is also on the box it arrived in as well as the Main Menu > Settings > Device Info page on the receiver if it’s been installed installed before.

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Numerous times. It happens all the time. I just wait for it to come back on and carry on as usual. If it’s a bad sensor and totally off I call and get a new one. The first day is usually terrible for me. But I have off numbers constantly. I could never bolus off Dex without finger sticks. Today it said I was 115 when I woke up then going up to 130 before I ate- did my finger stick and it was really 177. Totally messed up my whole day because I chose to trust Dex instead of back it up with a finger stick.

Fairly rarely with the G5. With earlier versions of Dexcom it could get pretty horrific.

Caleb gets about 10 days of use from a sensor pretty consistently. It’s at this point when ??? start to appear and we change it out.

Water also was more of an issue with older versions - or maybe it’s just that ??? was more of an issue and I considered water logging more often and dried out the sensor to try and solve it.

I can’t remove my transmitter without removing the whole shebang because I cover the sensor and transmitter with Opsite Flex-Fix. Yes, you’re not supposed to do that, but I rarely ever get the dreaded ??? and wear my sensor for at least two weeks. Because I prepare the site beforehand, I don’t have any problem with itching.