Dexcom 8Gxxxx restart-block and pre-soak

The low energy Bluetooth sucks. I’m with you in regards to a rechargeable battery like Medtronic incorporates into their transmitter. This would put a huge dent into Dexcom revenue stream of having to purchase a new transmitter every 3 months.

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Im on the Dexcom6. I have not needed to order for a while. I’m assuming the 8g is a new

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I agree. The only issue that might arise is inability to deploy new firmware in a timely manner. All the actual number crunching and algorithms reside on the microprocessor in the transmitter. The receiver and/or phone just receive the data and format for the screen. Of course that’s also why we’re having the issues we have today - Dexcom updated firmware to prevent restarts. I imagine in the future they might update for a safety and/or performance improvement. But I’m not holding my breath.

iPhone. Dropouts mostly seem to occur at home overnight, usually early morning, but also in the evening sometimes. It’s really hard to find a definite pattern, and I know enough about Bt that I know it can be flukey. Other BT devices can interfere, and we have several in our house, not to mention its a big condo in an urban area and a lot of other signals are zipping about all the time. But it does seem like this particular transmitter is having a lot more drops than my previous one, which had a lot fewer than any G5 one I’ve had.

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I was amazed to learn about all the apps that are using an iPhone’s BT in a clandestine fashion. Sure doesn’t help with clean BT communication.

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The newest transmitters that Dexcom is sending out (8G) have a software update that prevents restarts. You can tell if your transmitter is an 8G by going into the settings on your app and looking at the line labeled Transmitter. It will say either 80xxx, 81 or 8G.

Today I accidentally stopped my G6 sensor via my Tandem pump - so frustrating that I accidentally hit buttons in the right order to do so.

I tried to restart my sensor and my normal trick isn’t working (do no code, restart in 15 minutes with original code). My transmitter starts with 81H… any suggestions there??

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try this link

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Question for @DrBB. I’ve had a lot of communication problems. One issue with data getting lost in the middle of the night (that I find super annoying) is that as soon as communications are restored, Dexcom back fills the data so that it appears as if there was never any communication failure. That makes it hard to look back in the record and show people the frequency of failure. Has this been an issue for you identifying failures? Sometimes I sleep through the failure. Upon waking, it looks like it never occurred.

I just found a major source of my comm problems. But, its not gonna have impact for you since I’m on a different system.

I’m using a firefly transmitter now. Just started it. I’ll let you know how it goes.

One middle of the night issue that I had this summer was loss of internet because we had tons of thunderstorms this year. It happened so frequently here, that it was easy to identify the source of the trouble. It happened once this week. In order to restore comm, I had to manually go into the phone settings and turn off my home network connection, and turn on my phone’s internet data plan to run through that. Storms have been so bad here, that once I lost home internet service and phone cellular service. BT was my only option then.

I think that there are some people we could write to if we think the source of the problem is flaky BT connection and interference. The local guy who looked at my system to help me troubleshoot was VERY suspicious of the BT. That ended up not being the main factor for me. But, it may be for you. Do you have fluorescent lighting in your house?

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I’m a little confused about why a loss of internet or wifi would affect your CGM connection, since Bt is a direct connection between two devices, no internet or cellular network involved.

Is that to act as a signal boost? I’m not really familiar with it.

But bottom line: Wifi, cellular, and BT are all just protocols using different frequency bands in the radio spectrum, so any interference in that realm could cause BT problems. I definitely have a persistent glitch in connecting between my iPhone and my BT headphones in our apartment, and it goes away at a certain distance down the hall, so I know something localized within our space is capable of causing BT issues. Re fluorescents, we mostly have track lighting with LEDs, but we do have some of those fluorescents that replace old fashioned screw-in lightbulbs. Hadn’t thought of those as being a possible interference source, but…

Its runs off BT, but its data also flows through the commercial Dexcom app. Data gets uploaded to their servers through an internet connection.

This stuff gets tricky because we all have different configurations now. For me, it might be a bigger deal because when BT comm with Loop goes down, Loop can get data through internet. But, sometimes both go down.

Firefly is the nickname for the transmitter that you were using, although you might have a different model now. My old model was the 81XXXX. Now, I’ve changed to your 8GXXXX model. For a while you were listed as the only Tu user with that model.

Yes, that definitely sounds like a crowded bandwidth. Sounds like the right diagnosis. You wouldn’t see issues with an omnipod insulin pump (although thats similar communication type) because its on a less crowded wireless bandwidth.

I’ll try reaching out to someone who might be able to help with this. Might not get a response, but I’ll try. Maybe we could identify the source of the interference. But, I’m suspicious of the lighting.

You don’t have plaster walls in your building do you? Thats a common source of interference because there is metal grating below the plaster that forms a sort of Faraday cage. It often causes problems for the police when they want to eavesdrop on your wifi communications.

This is what some people do when they get mad. Sometimes people have to report the source of the interference to the FCC.

DrBB - just want to circle back to presoaking with the 8G transmitters - you have been doing it regularly without issue and with the stability we all experienced with the older versions ? I haven’t done it yet (guess I’ve been too lazy) but have been getting erratic reading early on for some sensors - in fact I’ve had 3 recently replaced. Hoping my current one (placed last night) will settle down - calibrated it twice about 12-14 hrs following insertion.

Weirdly, my most recent attempt, a 12-hr presoak, came out of warm-up perfectly stable and stayed that way for 8 hours, through a pretty high carb lunch and a peak BG at 170, but then 8 hours in, with a low-carb dinner, did the weird zig-zag I’m going high, no wait, I’m going low thing the G6 seems to do. So next time I guess I’ll just pull it together to do a full 24 hour one and see how that does. Everyone’s experience (YDMV) seems to be different with these durations. The one constant for me seems to be that if I don’t presoak at all, I’m going to see the zig-zags for the whole first day. With the G5 I knew first day results were a bit buggy, but only saw these really erratic readings if I’d hit a blood vessel on insertion—a pretty sure sign of that. OTOH, overall the G6 is way more accurate for me than the G5. I rarely felt confident bolusing without testing on the G5, whereas (after it settles down) I do that all the time with the G6 and hardly test at all. So it’s a tradeoff.

Thanks for the update - but no issues that lock out the sensor (ala restart).

Yup, true dat. Haven’t tried the Bluetooth “forget” method yet, but also not sure if it’s worth the effort for me.

The one thing about it that DOES suck is that I found doing a sensor restart worked as a cure for the erratic thing when I had a really persistent one (no pre-soak). Came out of the re-start warmup perfectly stable and stayed that way.

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@DrBB did you manage to do a full 24hr restart? I want to do it, but am worried about the “no restarts” / no insert trauma being triggered…


Hi @jake2.I assume you meant full 24hr “presoak” not “restart.” Haven’t done one that long yet. I was getting set up for it, but at the last minute this new restart method that’s going around turned up, so I decided to try that instead. And it works—yay!

And welcome to TUD–hope you stick around!