Tslim isn’t automatically entering BG when I tap Bolus

Just noticed when I tap Bolus I also have to manually enter my BG reading as well as carbs to get the pump to calculate a dose. Why?

I’ve got Control IQ turned on. I’m paired via Bluetooth. App turned on. I don’t use the app on my iPhone to Bolus but I just checked and if I did I’d need to enter BG manually there also.

I just RTFMed and it says auto populate won’t happen if I don’t see a CGM trend arrow, and I don’t. So now I’m trying to figure that out too.

I don’t recall doing anything to stop the pump from automatically populating BG.

What am I doing wrong, please? I can work around it of course but I shouldn’t have to, IMO.

In my experience, the lack of a trend arrow occurs when my CGM is bouncing around and having trouble giving accurate readings — usually at the beginning or end of a sensor session.
Does your CGM seem to be working well?
Has the problem persisted? Often the CGM soothes out on its own (especially if the problems are in the first 24 hours of a new sensor.)

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You didn’t do anything wrong. The pump is forcing you to be more active in the dosing decisions because the CGM data is unreliable. Dexcom doesn’t display a trend error when there are statistical errors in the data, I.e. it’s too jumpy. You may not even see the jumpiness, since Dexcom uses a smoothing algorithm to display pretty and meaningful graphs, but the lack of trend arrow is telling you the system has no confidence in the data it’s displaying. The formal literature says you have to fingerstick for dosing decisions when there’s no trend arrow. And you’re right, you shouldn’t have to!

You can change the sensor and make Dexcom send you a replacement. You may have to fudge the form a little since they don’t have “this sensor isn’t good enough for my pump automation to work flawlessly” as a failure option". Personally, I would pick whateber the option for inaccurate readings is tell them whatever they want to hear the the follow-up questions. Or you know, your food to to stick it out and hope the sensor settles down. Maybe drink some water…

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Sounds like a Dexcom problem and not a Tandem problem. When my CGM is working well and data is coming in normally, it will populate automatically with my blood sugar. If my line is all wonky for whatever reason, the pump doesn’t use that information to calculate a bolus because it doesn’t know if it will need to add more insulin or take some away etc.

Good answers all. I agree forcing me to stick when there’s no relic data is exact the right thing to do. Thx.

What a timely post! I noticed the same thing this morning, having just changed my Dexcom sensor last night. As the day has progressed, my pump is now showing BG on the bolus screen.

The trend calculation requires at least, I think, at least 3 readings in a row. So if the signal dropped, or you restarted a session, it’ll take at least 15 min to get a trend or calculate a bolus using bg.

I’d like to know how the x2 decides the readings are unreliable. Is it deviation, inflection, what? If the smoothing algorithm can make unreliable readings look flat, that seems like a problem to me.

If the pump thinks the readings are unreliable enough to exclude them from their control algorithms and require a finger stick, why doesn’t warn the user! This is the pump that requires us to acknoledge that there was a high bg 8 hours ago.