? About?

Hi all I put a new sensor in the morning of the 7th and this evening I am getting the ??? Is this a defect kind of thing prior to the 7days. Should I be calling it in? Has been like this for a while now and I only have the one sensor left.

It's most likely the transmitter is not connecting well to the sensor. Try removing the transmitter and cleaning the two small silver connectors with first a pencil eraser, then with a dry cloth. Put it back and see if that makes any difference.

The system may tell you that it cannot provide a sensor glucose reading. When this happens you will see either the ??? glucose reading error icon or the hourglass wait icon in the status area. These symbols mean the receiver does not understand the sensor signal temporarily. These symbols are related to the sensor only.
Wait for more prompts, and do not enter any blood glucose values when you see these symbols. The system will not use a blood glucose value for calibration. Often, the system can correct the problem and continue providing sensor glucose readings. If it has been at least 3 hours since your last sensor glucose reading, contact Technical Support.

Usually when I get the ??? it is after a shower or I have gone swimming and it is the result of water underneath the transmitter. If the sensor is in a convenient place I remove the transmitter and dry it off with a towel and dry off the sensor and replace the transmitter in the holder. It normally comes back online pretty quickly. Some people use a low setting on their hairdryer to get rid of the water.

thanks for the explanations, It was showing the ??? for more then an hour, I called tech support and they are sending me a sensor, (very cool), no water issues, just seemed to happen around 7pm and did not come back on. I stopped the sensor and restarted it to see what will happen, have about a half hour left before putting in my readings. hope it works, or putting a new one in in the morning as I have to go out of town to see my Endo, first time seeing her since I got the dexcom.
p.s. can I take the transmitter out and clean anytime that it is needed, and will it start the 2h wait to calibrate again or just keep on ticking?

well the ??? keeps coming back, now 2:49am so later in the morning will put a new sensor on since this one is getting replaced anyways, not sure what went wrong, no signs that it was going to go poof. going to have to order more since this will be my last one. sigh. at least I got a few extra days from them except for this one, wish they would last more than 10 days since I pay out of pocket for them. Thanks for your suggestions.

Although it is not recommended - you can snap the transmitter out briefly to dry it off and snap it back in without having to do anything as far as calibration goes. The transmitter does not search for a signal continuously, just once every 5 minutes so what happens the remaining 4 minutes and 59 seconds is no concern.

Thanks Clare, ended up having to replace it, wish I hadn't have it on my upper stomach, hate it there. LOL we will see if it works though, calling on monday to order since I don't think they are open on the weekends

Clare, FWIW if you have an alcohol swab, that would be better/faster since alcohol literally removes water.

Thanks, yes I do use alcohol pads to do the chore, but only if I have one handy. To be honest I haven't gotten the ??? in a very long time. My current sensor is on day 16 and the one before that was on day 26 when it finally started with the ???.
One other thing I have read from people who use the Dex if they get the ??? it can sometimes mean they're dehydrated. They (or their children) drink a lot of water and it seems to come back on line.
I have learned a lot from parents of T1 kids and now that the G4 is approved for pediatric use there will be an even larger resource for information.

You can try using my trick with your sensor: