Timesulin cap wigging out

So several times over the past week I’ve picked up my tresiba pen for my 1x daily shot and noticed the timer on the timesulin pen made no sense… eg I knew I had last taken the shot 22-26 hours prior but the number on the cap would read something very different, say 2 or 4 hours… as if it has been reset by the cap being removed from the pen. Just now I picked it up and it said 2 hours and ten minutes, even though last time I’d used it was sometime around this time yesterday… then while I was sitting there looking at it, the numbers started flashing and then reset to zero… without me taking the cap off.

So clearly it’s malfunctioning… has anyone seen this before? Is this maybe what starts happening when the battery starts to die?

Another example of why I don’t like gadgets… once I start to depend on the I get worried about how difficult it’d be without them…

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How old is the cap? It could be a battery. Or maybe the pen cap wiggled loose.

That’s the problem with those pen cap things. If the cap comes off, it resets the timer, even if you didn’t really use it.

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There’s no way it wiggles lose… it snaps on there positively… it’s maybe a year old or so. I’m not sure how long to expect the battery to last.

I thought their cap was supposed to only last a year, and when the battery dies you have to purchase a new one. I thought that was their business model. Certainly sounds like a battery dieing

From their website:


Must of not been fading.

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The other thing is that there is a small metal switch inside that engages when the pen is attached to the cap. That is the switch that activates the timer.

That mechanism could be loose or starting to wear out. So it is possible that even if the plastic cap is on tight, the metal switch inside might be wiggling on and off, and reactivating the clock.

Either way, if it is not working, bail on that thing and get a new one. And then dissect the old one to figure out what the problem was!

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Yeah… I think it’s acting more like a switch malfunction than a battery failure… anyway, I do like them when they’re working correctly. Only $10 on eBay— just ordered a new one

Cut it up and see what’s going on!


For some reason I can’t find my dremel… It’s got to be around the house somewhere but its been MIA for months

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Same cap has been working flawlessly since I got home. I was on a ship while it was having problems… can’t help but wonder if the mild vibration or something like that was a factor…


Had one where the battery clearly died… display just got more and more dim over about a week until finally it died. So I pried it open. It popped open quite easily and cleanly actually… looks like it had basically been glued down but in a way that it popped right open.

That’s all there is to them. It’s an 1130 battery, and the pen presses the metal tab down to make contact and start the timer. Somewhere in the circuit there is about a 5 second delay built in so that just a quick peek at how much insulin is in the pen won’t restart it.

Ordered some 1130s. Electrical tape holds the cap back together quite nicely


And it’s alive again


I’m a bit irate in hindsight… I had just been bragging about what a great deal I found on eBay to get a timesulin pen cap for $8…

But I just made a dead one as good as new again for $0.73c… plus it has so much more character now


How can they go wrong by wearing black? :wink:

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If I cared I could have glued it and made it look brand new… but I intend on renewing this battery every 12 months for .73c preemptively so why bother with glue


So is it purely greed or are there regulatory issues that prohibit them from facilitating battery replacement?

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Don’t know… most people probably aren’t going to track down a special battery anyway

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In this case I think it has to be the business model driving this. The cap is supposed to last for 12 months, and the reoccurring revenue is going to be required to keep the business going. If they simply sell them with a replaceable battery it would be a short lived business, kind of like Tandem when they weren’t capturing the site money.

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Might be part of the revenue model.

Didn’t they get bought out by Bigfoot Biomedical a few years back?

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