Guardian 3 sensor

Yesterday my guardian 3 sensor had 1 day and 15h left before it expired. Well at around 945pm I was getting ready for bed and I looked at my number and the dreaded sensor updating alert was flashing on my pump. That is the 2nd time when it has done that. I think the next time it has 6 days left I will change it in the morning around 8am that way I won’t be doing it at 10:00 at night. Urrrrgh. Very frustrating!


Glad to see that I’m not the only one that has this happen with the Guardian 3 sensor. I never had this with earlier CGM system (Dexcom G4/G5 or the Libre2). I’m trialing the 770g right now - and the MM CGM is a bit of a step backward in installation to body, etc. compared to those 2. I do call in for replacement of sensor though online. Do you?

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Even though my sensors are paid for by the government I still fill out the form for a replacement sensor. If you type medtronic replacement sensor in your browser you will find it. I added it to my homescreen so I could find it easier.


I like your new profile pic, @Dee_Meloche. Its a colorful waterfall!

Thankyou. It is a picture of Niagara Falls lit up at night.

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They say that the more stable your bloodsugars the better chances it will go the full length. My S.O.D. is I have had most sensors last 6 days. I had a few that had just a few hours left. They say that the glucose oxidase on the sensor wears out faster when your sugars aren’t as stable.


Thanks for the replies Dee - didn’t have wifi the last 10 days - so missed being out of the loop with my fellow T1D’s around the world!! Good test of the Guardian 3 / 770g on a cruise ship - came back with no weight gain (I walk alot) - sadly - my DH on 3rd day - contracted Covid - and I didn’t (since I’m a mask / washy washy twit - but that’s me - and wearing a mask - no one can see all the food bits around my gob … that’s my excuse and I’m sticking to it ). Back home now, and he’s still testing positive - moi - Negative - and he’s back to feeling really crappola today after a long day of travel (he didn’t wear mask on original flight from Montreal - which I think is where he may have got the bug - I wore mine - but that me).

Main thing - I’d semi-nagged him for his 3rd vaccine shot before we left (hoping he gets the flu shot eventually too) - so at least his alive despite feeling like a limp noodle. Vaccines do work to help you not have the worst effects of this virus.

Psst - as others have commented - that NF pic is awesome. I hope to get there again soon. Last time was for a Friends for Life event - on the Canadian side - and Americans who attended said our side was the prettier one (less commercialized then the USA side - sorry).


Yes, it is very beautiful. My husband and I have never had covid. We were healthy the last 3 years. A guy at my husband’s shop had a cold. It spread to me and then he got it. His is way worse than mine. It has also been affecting my bloodsugars. I increased my carb ratios to compensate. My TIR is starting to look a little normal.

How is the Sensor updating doing now with the Medtronic 770?

Hey there! Going better for the sensor updating (aka calibrating) - and it’s actually lasting as long as it’s supposed to (7 days - but I’ve managed to retweak it to last to 10 days with accuracy). I’ve had to go off the AutoMode bit though - after 3 month A1c and being on the 770g - it went up to a point I’ve not seen since maybe 1990’s??? My Diabetes Team didn’t seem to upset by that and didn’t mention tweaking anything - but dang nabbit - I’ve since that visit - gone off & done my own “investigation” and now in Manual mode and getting things “purrfected” again in that area (I had done this a week prior to going onto AutoMode on the 770g - as it’s recommended by manual and users - what would I do without the DOC?!). Now my TIR is awesome and I’m experimenting with foods that usually might make me go funky wonky … and all good as I continue with trial of 770g with hopes that 780g arrives one day here - where hopefully I can get back into tighter range due to the updated programming.

That sounds very promising. I’m glad. When you say your “trial” with 770….is it truly a trial….as in you are trying it out to see if you like it?

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Yes - it’s a trial - the pump isn’t mine (not paid for … yet ). I have a feeling that closed looping - at least with this system - isn’t for me. My A1c has gone up since using this - while TIR is great - it’s “Medtronics” algorithm version - not mine. I’ve been told by Medtronic to hang on for 780 upgrade and I should see better results - but as of yesterday (I’ve been back in Manual mode since Jan 6/23) - after a failed sensor that seemed to think I was low and blood finger test proved otherwise - and then system refused to believe the number when it asked for calibration - and to change out a sensor less than a day old - I am back on Libre2 - less alarms (especially helpful when driving or in a meeting) - and so far - staying within my range due to being more in control in Manual mode. I think this pump is okay for someone who maybe isn’t as “into” their diabetes control as some of us are who like tighter control - but for someone who has been winging it on their own with pumping … I’m better off at the moment (financially wise) with either one of the other pumps folks have offered to me to use in the meantime (I am allowed here in Ontario to have a new pump since Animas Ping is finished sadly) . So I’ll wing it until I really know what my next pump for 5+ years will be … but then who knows … maybe I’ll change my mind - at least if I stick with this pump until upgrade made - I have 3 months to “trial / try” it out until I slap down the cash (actual value of the pump is under $2K - but when sold - $8K).

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I see. I hope things go well for you whatever you choose. I am in a similar situation. I’m on Medtronic and nearing warranty expiration. Trying to decide which route to go.

I am going to get my software update soon as Medtronic has already contacted me. The 780 looks great. There is no more lockscreen. Th menu on the pump is icon based. Less button pushes to perform daily functions. The algorithm is also better and there are 3 targets. 5.1,6.1 and 6.7mmol.

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Is the 780 a software upgrade to the 770? Or a completely new pump?

It is a software update. The first day was hard. My bloodsugars dropped pretty fast after eating. I decreased my carb ratios and because I went low through supper I went low through the night. I am going to make an appointment with my diabetes educator.

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I did the update to the 780G last week - and because I found the AutoMode useless for me (even the Medtronic CDE said the same thing and said - hang on for the upgrade). So I went in Manual mode for 3 months until the upgrade - so my basals were tweaked to purrfection (I’m abit OCD - which many diabetics who like to have under 6% A1c are the same). So, the SmartMode as it’s now called … wowza … smooth sailing - and I’m generally in 90% range with using the factory loaded 5.5 / 100 aim (we have 2 other options in Canada which are 6.1 and the original 6.7 - for Americans - just multiply by 18 :kissing_heart: ).

As you say @Dee_Meloche - so happy that the lockscreen is gone. And also improvement of what we can see on our smart phone screen has improved. Now imagine when we’ll be able to bolus right off of the Smart Phone … but so far … I’m not complaining. I’m hoping to be using this pump during sea trials in Atlantic Ocean in July … heading from Halifax to Rhode Island - so if any of you along the eastern coast - and know of a marina that doesn’t charge an arm and a leg - let me know - so far we’re glad we only have a “small” sailboat of 30’ and hope to do our usual anchoring - but incase of inclement weather (it’ll take about 2 weeks to get from Halifax to Rhode Island - maybe longer if I want to shop for pottery ) - at least we’ll have a safe harbour. Hoping to get back into blogging - and maybe vlogging - but we’ll see.

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So, I have been on the 780 for a little over 4 months. after tweaking my carb ratios and finding out what works for me I am getting anywhere from 88-97% on target. I am using 6.1 as my target. I still find that the guardian 3s are still a little inaccurate especially on the second last day. I will be happy when the 4s come to Canada. Hopefully accuracy will be improved and I won’t have to pick my finger as often.

Could I ask how you Medtronic folks like the Guardian Sensor? I left Medtronic for the Dexcom connection to Tandem pump and because then the Medtronic sensor was so difficult to put on. Has user friendliness improved any? Or you may not have been long time users. Thanks for any thoughts. Also the Dex is so accurate for me. My Endo NP wants me to look at the newest version of the Medtronic stuff but online I am not seeing what I need to. I’ll check youtube next.

The insertion process is the same. I use the guardian 3 which still requires calibration. Medtronic will launch the G4 at the end of the year, I heard. I use Hypafix transparent tape instead of the tape provided. It is easy! I apply 1 piece
to over the entire sensor. I round the corners so they don’t fray. For accuracy, I find the last day it looses some of its accuracy but all in all it is a great system. I am holding out a lot of hope for the G4!!:crossed_fingers: