Pump malfunction

My t:slim pump was at 30 something units this morning and I got to class and it said it was empty. I didn’t bolts anything, I didn’t prime anything, nothing. I don’t understand what’s going on…maybe a leak in the tubing or cartridge?


I recommend you call technical support at Tandem.
Is there option on pump to check bolus history?

I have not heard of others reporting this, I use medtronic pump.

I second the idea to call Tandem. We have been using the t:slim and only noticed something unexpected when my son let the battery discharge completely. After charging, it went back to its happy pump self.

1 Like

How often does it need charging ? In extended power outage, how would you charge it ? We had a 12 hour outage a few weeks ago.

Battery lasts about 5 days if paired with CGM and about a week if not according to my pump trainer. It charges via a typical micro USB so I could plug it into car charger or external battery pack if need be.


Everything @glitzabetes said is true. Since we live in an earthquake zone, we have multiple batteries (Li-ion and Lead Acid) and a small solar panel. Enough to keep us going for few weeks in an emergency. Of course, if it gets past that, we have syringes.


@Thomas, have you seen this problem before?

Could you have misread a 3 as 30?

Did you have a sudden drop in BS? That would have been awful. I had a friend who was traveling with my husband and I; she asked if I had any extra insulin on me (we were in the car and she didn’t want to have us pull over for her to unpack hers). I gave her my vial and she proceeded to fill her pump - I think a medtronic. As it turned out, she didn’t disconnect (I don’t know much about pump processes other than OmniPod) and when it primed, she got all of the insulin. Not 10 minutes later she was 24 via blood glucose check and I was pushing juice, soda, food the rest of the night. Anyway, you didn’t mention a sever drop, so I’m hoping that didn’t happen.


That is absolutely insane. That is a person who should not be using a pump. That is very basic.
I can’t even imagine how anybody would not know this. Almost like the person never had any training, never read any manuals, never spoke with anybody who uses a pump, just got the pump handed to them the previous day on a street corner and was using technology they were not qualified to use.

Completely horrifying as to the lack of obvious knowledge as to how the pump operates.

1 Like


Certainly looking through the logging history of the pump could be instructive.

This should also be a call to Tandem Technical Support.

Some possibilities are

  • potential user error in which case Tech Support can provide additional information and instruction.
  • potential pump malfunction in which case Tech Support can do their thing and decide the best course of action.
  • another possibility which we may not consider but which Tech Support may have experience with

(When something goes wrong, it is IMHO better not to discount an option until the cause is positively determined. Saying it could not possibly be user error or saying it could not possibly be equipment malfunction can potentially lead one down the wrong direction. I think everything is a possibility until the cause is found.)

Tandem main page for all of their manuals:

There are of course numerous warnings in the Tandem t:slim X2 manual (User Guide with Basal-IQ).

Potentially relevant:

DO NOT remove or add insulin from a filled cartridge after loading onto the pump. This will result in an inaccurate display of the insulin level on the Home Screen and you could run out of insulin before the pump detects an empty cartridge. This can cause very high blood glucose, or Diabetic Ketoacidosis (DKA).

That being said, we have removed insulin from the pump when we were “out and about” and wanted to do an MDI to bring down a high. However we would only be removing 3~6 units for a manual injection and would never add insulin while the cartridge is loaded onto the pump.

Another warning would could be relevant:

ALWAYS twist the tubing connector between the cartridge tubing and the infusion set tubing an extra quarter of a turn to ensure a secure connection. A loose connection can cause insulin to leak, resulting in under delivery of insulin. This can cause high blood glucose.

And a completely non-relevant warning that was just too much for me to resist cutting-n-pasting

DO NOT allow small children (either pump users or non-users) to ingest small parts, such as the rubber USB port cover and cartridge components. Small parts could pose a choking hazard. If ingested or swallowed, these small component pieces may cause internal injury or infection.