T:Slim Malfunction 255

I just replaced my Dexcom G6 sensor and, one hour into the warm-up period, got a Malfunction Code 255 - Bluetooth Hardware cannot operate. Does anyone else have experience with this? I get on a plane in less than 12 hours and am really worried about being without a CGM for the next week. Any Tandem tech support just goes to an automated line asking me to enter my number…based on past experience, they can take hours or days (yes - days!) to reply. Is this something I can correct on my own? Or am I in real trouble here?

Can you call Dexcom? 1-844-607-8398

I can try, but I am pretty sure that they will refer me to Tandem because I use my pump as my receiver?

Here’s hoping you have success. I use the G5 or I would try to help you. Also, I tried to see if I could find the error code online and I didn’t have any luck. :frowning:

@sarakay88 Tandem Support is 24/7. I can vouch for that unless they have made recent changes.


(877) 801-6901
24 hours/day
7 days a week


That’s the first I’ve heard of that. Maybe I did make a good decision by ordering a 670 (no plans to use their sensor or automode) and cancelling the X2 which tandem didn’t process quickly enough while my current pump is broken. I like companies that give good support.

Tandem have excellent support. I’ve never called them and have been put into an automatic message box.

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877-801-6901 worked for me just fine for Tandem customer support after midnight on a Sunday evening last week. If this is true, it would be something brand new. Are you sure you went to the customer support line and not another line within the company. Should be option 1

Sorry - Last month, not last week