Dexcom G6 transmitter

Hi everyone,

I’m coming to the end of my first G6 transmitter lifespan.

Are there any links or descriptions available for restarting a transmitter that is one of the newer editions?
Mine is an 8G, and not I’m sure whether tutorials for 81 or 82 transmitters are applicable.

Also, while on the topic, what is the best technique for restarting sensors?

Many Thanks

Unfortunately, there is no way to reset any G6 transmitter with a letter in the second position. Sensors can be restarted, but not newer transmitters.

Depending on your software, though, you can get extra life out of it. Dexcom software won’t let you start any sensor with a transmitter more than 90 days, old. You’ll get 91-99 days life max if you use the Dexcom transmitter and/or app. If you use the T:slim X2 pump as your primary receiver, it relies solely on battery life, not a set number of days. There are theories that you can’t start a new sensor after either 100 or 110 days on the X2, but I haven’t seen that verified anywhere. 3rd party connection apps, like Xdrip, don’t have a hard stop at all. They’ll keep collecting data until the transmitter dies.

Unfortunately, once the battery dies though, there’s currently no method to successfully replace it and reset the software. I actually tried with an 8G before I knew the “firefly” sensors were different. They use different batteries in them. I couldn’t even get the battery out, despite successfully removing the plastic housing. The battery is cased in something approaching tin foil that disintegrates under the lightest touch. You can’t pry it free from it’s soldering.


If you don’t use dexcom software you can use it till the battery dies. There are a few apps out there but they are no longer on the AP stores

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I think that a 8G is a ‘Firefly.’ I think we have been restarting those for a while, but then we couldn’t, but then we could again??? Let me check…

Conversations here: The dread G6 session-restart block is here
Our conversation there is super old and long.

Your supposed to use the BlueTooth Unpaired method?
Let me get confirmation from the others, but the link is here:

@DrBB @MM1 @maninabag @talldrinkofwater @Marie20 @BradP

This post is a little newer - 7 months ago…

Here’s a video from January using X-drip restart on a firefly:

If it can be done on Xdrip, it can be done.
Nope, don’t use the 81 or 82 methods. All methods are dependent on the transmitter model. Maybe someone can make a new, up to date video. Brad would probably do this for ya if he has an 8G. Hey, @BradP! I think he uses X-Drip, though.

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But the OP asked about resetting the transmitter, not restarting a sensor.

I restart sensors all the time, but it’s not possible to change the battery on newer transmitters


Thanks for the links, I do use xdrip so happy to hear I can just keep going post 90 days.
How many days on average does the battery last after 90?

Thanks Robyn,

What technique do you use for restarting sensors?
How many extra days do you get out of it?

I tend to leave the sensor on just an extra 6 days after a restart, it starts losing readings on xdrip and my t slim x2 far too often after that.
Maybe thats down to a flawed restart method though.

I restart via the pop the transmitter out and wait 15+ minutes way, then start a new session. I thought that was the only way that works on the newer transmitters.

If you’re successfully getting a restart, I highly doubt a different method will prolong your sensor life any. Your extra 6 days sounds fairly typical
Plenty of people struggle to even get 10 days, let alone extra.

My theory (I didn’t first propose it, but sounded right when I heard it), is that the flatter you maintain your line, the longer the sensors last. I swear, the high swings seem to eat up extra reagent. So long as I can keep my GVI less than 1.25, I have no problem getting 30+ days. I seldom restart a sensor that’s more than 30 days old, since I expect them to fail sometime in that next session. My record was 42 days, though. On the other hand, my shortest was 14 days, and I was definitely struggling with control then.


Agree. But would add that I think staying well hydrated helps too.

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Cheers, good to know others have got similar results.
This may show a lack of knowledge on these compounds, but if available, could more reagent be applied to the sensor?

The first dexcom and medtronic sensors lasted only 3 days, so certainly longer wear time has been increasing. Abbott freestyle Libre is 14 days, and the next dexcom G7 I think will also be 14.,2020%2C%20with%20a%20larger%20commercial%20launch%20in%202021.

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The sensor is embedded under your skin, so I can’t imagine how you’d apply more reagent to it. I’m also pretty sure it’s composition is a tightly guarded secret.

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I’ve gotten to 110 days on the same transmitter with my Dexcom receiver. I was surprised!

My first Dexcom G6 transmitter lasted 39 days…not a good start. Dexcom replaced the transmitter at no cost but it took them 8 days to get it to me. That part was not fun at all. To those of you getting 90+ days, I now have something to look forward to and work towards.

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Is it possible to extend the life of a transmitter by moving the transmitter over to another receiver we will call receiver #2 after the 90 day warning? I was thinking that would work because the 2nd receiver has never used the transmitter code before and think it was new and even the sensor would be restarted at the same time?
I guess the one issue is whether the receiver uses both a 90 day timer and monitors the battery voltage to decide when transmitter needs to be changed, whatever comes first? For example if it senses the starting voltage of a transmitter is to low it may not allow you to even use it?

The transmitter stores and updates the number of days. The receiver just reads it from the transmitter. This allows a phone and a receiver to both show the correct number of days.

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Thanks! Never thought of the transmitter storing the number of days. An unused transmitter must be in some type of hibernation to conserve power but once it starts to make readings the day counter starts, does that sound right?

Correct, kinda like sleep mode. When you enter the transmitter code (unique to each transmitter) into your receiver or phone, and pair it, that connects to the transmitter, and I assume it has logic to know to start/update the day counter on transmitter for initial day count. Then transmitter increments each day, so receiver and phone will get/confirm info from transmitter.

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No. There is a timer that starts ticking on the transmitter at first use (first time attached to a sensor?). If you do a raw download of your Dexcom Clarity data, you can see that every 5 minutes you get a glucose number, with a “wall clock” time (the time set in the receiver) as well as a “Transmitter time” (seconds since it was first activated).

Some “third party” Dexcom readers (e.g. xDrip) do not know how to process transmitter life/sensor life messages from the transmitter and can show some wonky stuff.

Below in my Clarity export, is the transition of transmitter time from 8703673 (100.7 days) to 7573 (a little over two hours) when I last changed transmitters in December.