Dexcom is obviously under pressure to reduce the number of replacement G7 sensors they send out. I put in for a replacement and it asked for the Serial Number SN of the failed sensor. Trouble is, they don’t label it as SN on the box or anywhere else. It’s the number that follows (21) on one of the box ends. They replaced my sensor as a “goodwill replacement” --limited to three per year–because I had put in the Lot Number instead of the serial number. Then they sent a second email to EXPLAIN WHERE THE SERIAL NUMBER IS! (shouting) They even have a web page up to tell you where it is. But nothing so simple as labeling it SN on the box. Looks like a scam to me to discourage requesting replacements. They also say you have to call tech support now before replacing. Somebody in corporate leadership has told them to discourage the replacements. Just as the FDA has exposed that they are sending marginal sensor batches out to us. The one I replaced was the worst I have encountered recently. I have been using Dexcom since the G4, but when competition arrives I am going to check it out if they don’t treat their customers like this.
The same thing happened to me a while back. It’s not clear to me that identifying the serial number correctly will help but maybe it will so for those who do pictures more than numbers:
That’s what you see: look for (21), second line from the bottom.
For those who do numbers the “transmitter ID”, as xDrip+ calls it (it’s the pairing code for those who do computers) is the 1249 at the top. The actual bluetooth ID of that transmitter/sensor is ED:12:55:8A:9D:58. The blueteeth “Device name” is DXCMKA.
On an Android 'phone the way to get the latter is to to go settings/bluetooth[sic: only one apparently] and check out the (i) entries until you get a match on the xDrip+ report of the bluetooth’s ID. In my case it was at the top, a possible explanation is that Android lists bluetooth devices in order last seen but curiously my Omnipod (Dash) does not appear in the paired devices list.
it’s super annoying when something that should be simple becomes a headache. I’ve been there too, and it just makes you wonder if they’re really making it easier for everyone.
If only there was an app on your phone that already knew all the information about the sensor, its readings, errors, insertion time, serial number, etc.
I honestly always forget it displays the SN on the app (and actually calls it “SN”)! Under Connections / Sensor / Sensor for anyone looking.
Ya I always take a screenshot of the sensor info with the serial and lot number and such at the beginning of a session.
I think if the sensor suddenly fails and the app says you have to start a new session the info isn’t available anymore. I had this happen a few months ago so this is from a distant memory?
Ooooh yes, you may be right about the sensor info disappearing… And I can never get my Dexcom app to let me screenshot either, I think it’s some “privacy” setting the app uses. 
Good points!
Looking back at my post I see that it might have been seen as criticizing the users of the G7, while I meant to criticize the G7 app.
What I should have said is that if the app knows that the sensor has failed, perhaps it could offer to send all the diagnostic info to Dexcom and even offer to have a replacement sent to you automatically.
@ned Your suggestion is right on the mark! Offer to send the data to Dexcom! Per my discussion with one rep, they have it already, so just use it!
That would be awesome!!
Don’t see it happening 
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