Weak Signal Questions/ Minimed CGM

For the last month my CGM keeps registering WEAK SIGNAL which eventually moves to LOST SENSOR, even if I move the pump closer to the transmitter. I have contacted MM and they will replace it "when it is in stock."

I can wear my pump in the same place for hours/days with no problem then it does the Weak Signal thing. I usually move it into my bra and it is inches from the sensor. It will eventually go into LOST SIGNAL and then work back to a 2 hour wait to reprogram a calibration. This is very unusual.

Anyone have any ideas about why? Fully charged, lots of different sensor insertion places, everything is normal. Thoughts?

I find I get weak signal when I am sleeping or at work, where I sit for a period of time. I think the lack of movement affects the sensor, but it is just my theory.

here is some other thoughts:
a) sometimes there can be interfering transmitters/signals in your space.
b) does this happen sitting in car driving it somewhere else.
c) do you have any trick devices apple/cell/bluetooth running close by?
d) are issues happening in condo/apartment where there can be a ton of interfering signals?

It has happened in the car, when sitting and reading, when cooking a meal--lots of different scenarios. And it is always surrounded by trick devices--phone, Kindle, laptop. Being or moving away from them does not help.

Oddly, even when placed right next to the transmitter, the pump goes to lost sensor. Then it goes into 2 hour warm up mode when I hit find lost sensor.

I have had this happen very infrequently over the years, mostly when I was away from the pump, such as in the shower. It always went back to normal, once I put the pump back on and within close proximity to the sensor and did not go to lost sensor or the warm up.

Call Tech Support......;-)

Is the battery on your transmitter weak?...needs replaced!

I never use the find lost sensor for any reason but to test trans with the little blue thingy. If you loose the sensor just try a regular start and do a cal as soon as it finds the sensor. If you are getting the two hour restart (warm up) then the transmitter is resetting...like when you unplug it from the sensor...your pump cannot reset the transmitter clock. when you plug in the sensor it starts the clock and a two hour countdown and it only does this one time during the 168hr timer cycle ( referred to by some as the death timer) and this cycle is reset when unplugged and/or placed on the charger. If you are getting the 2 hour warm up then your trans has a loose connection inside or is coming unplugged from the sensor.

If the pump comm port connection is bad then the pump will loose the sensor but you will be able to do a restart and calibrate as soon as the pump reestablishes a connection, you will not have to wait for the 2 hour warm up.

I have had old transmitters that would lose the connection and have also had pumps with (code64) or bad com-port.

How old is your sensor, if it's 3-4 years old, maybe it's time for a new one? I had some issues w/ readings all over the place and called them and they said "it's probably time for a new one" or something like that, it was under warranty so it was swapped out.

Replaced the transmitter last spring.

The weird thing is that it happens and once I get everything going again, it works just fine. It may not happen again for days, and by that time the sensor is in a new spot, the transmitter is fully charged, etc.

That was very useful information, John, about the restart. I did not realize it resets.

Been having the same problem. I have been a sensor user for 6 years. My current transmitter is only 8 months old. Calling Medtronic will only give you headaches. In one day from three different techs, I was told "scar tissue", "my new mattress", "coming dislodged from skin" to my favorite "a passing police car" is causing the messages. I spoke to a supervisor and told them that the latest batch of soft sensors are no good and there are numerous online complaints about them. In other words, "too bad, so sad" but they aren't doing anything about it.
Make sure you call and register with minimed every error message you get.

LOL!! I got the passing police car, too. I scoffed at that one!

I told her I lived on a big hill on a dirt road and cops haven't been here since Prohibition ended. I got upset and told her that I wasn't mad at her personally, but hundreds of users have complained of this error in the last 3 months. How many calls from us until they recall the soft sensors?

I'm pretty new on the pump & CGM (about 2.5 months), but I started seeing the "weak signal" notice quite often. I found that the transmitter had apparently not charged well. So, I took the sensor off, left the transmitter on the charger for at least a couple of hours, preferably overnight. I generally turn the sensor settings to "off" on my meter during this time.

When I do this, every time I have had no more issues with "weak signal" or "lost sensor" alarms. Not sure that it's a direct correlation to what you've got happening, but it might be worth a check.

Glad you solved your problem. It can be daunting to say the least in the first 6 months. Our problem is that our sensor goes from Weak Signal straight to 2 hour start. For no reason. In the good ol days of last year, you could wear a sensor for almost one month without getting a weak signal.

trauts--it should charge fully in about 20 minutes. I have been doing that for 4? years with no problem. I try really hard to keep the sensor active all the time, so (on the 7th day) I insert a new sensor the night before so it can "rest." Get up in the morning and charge the transmitter, then insert and head towards calibration. I am usually unsensored about 2 hours.

Personally, I think the problem s related to the pump reception. As I said, I have had more problems when the pump battery reading is low.

Good idea, Spock. I've put one in a little early before taking the transmitter off the old sensor, but wasn't sure about how long to charge. I think the site said 1 hour for 3 days, 2 hours for 7 days. All I know is that the issues stopped happening when I charged the transmitter.

And dgarrison, I would have it go to the 2 hour start from Weak Signal when this happened. I just assumed it was related to the same issues from a weak battery.

If you do have a WEAK SIGNAL go straight to START, call MMed immediately and have it logged for their records. Hopefully after enough complaints, they will make them like they did in the past.


I plug it in when I get up. About 30 minutes later--depends on morning activity--I attach the transmitter to the sensor, cover it and shower. The charge lasts almost exactly 7 days. But when you hit the 7 day moment, I will get weak signal.

That is OK, as I know why. It is the unexplained stuff at weird times that freak me out.

dgarrison- cannot find START. What are the steps to get there from the main screen?

I am late getting a reply to you and you may already have an answer. My CGM had the same problem and it was only through good fortune that I learned from a nurse educator, who also has diabetes and uses a CGM, that the monitor was SHOT! It was not me that was screwing up; the machine was simply dying. I was able to get a new one and the problems vanished. I wish all the nurses were wise like her, but finding one was an accident.