Dexcom USB cable - rewired to charge my receiver unit

Hi all. I am new to this forum but thought I would post something helpful. I am a type 1 diabetic and I use the dexcom seven CGM. Recently I noticed that my receiver unit stopped charging. I called dexcom support and they said they would send me new charging cord, which would take a week to get to me.
Unsatisfied with this, I went to every electronics store in Colorado trying to find a compatible charger. (FYI there aren’t any, dexcom uses a very proprietary plug) so I was out of luck and assumed I would have to back to my old “test 10 times a day” routine. Then it occurred to me that the USB cable supplied with my dexcom might somehow be converted to charge my receiver.
(it doesn’t by default, and I have no idea why). So, I pried opened the end of USB cable with a putty knife and saw four wires. (red, black, green and white) I knew that the red wire is supposed to be the 5 volt power supply in a USB cable, but I compare where that wire was positioned to the now useless power cable dexcom was replacing.
Turns out the red wire in the USB cable wasn’t being used for power in the USB cable (no idea why) so I just snipped it, hooked it on to the same pin position as I observed in the actual power cable and viola, it started charging my receiver! So I closed the plug/tip enclosure and had a functional USB charging codd.
I have no doubt this is not approved by dexcom and don’t pretend to be an electrical engineer, it just worked nicely for me.

You saved me!!! My charger died after 2 months or so of slowly degrading. Been calling dexcom for a couple days and haven’t been able to get ahold of them. I pried off both the USB and Power cables Proprietary ends (slide a knife in, rotate knife to unlock plastic from metal connectors, then pull the plastic down, once the metal box is exposed its easy to pry open and see the red wire our man is talking about. The red wire needs to be cut since its soldered… After you carefully cut it strip off enough of the wire’s insulation to expose. Then push the red wire to connect to the bottom left pin. If you’re not sure about the correct pin be sure to open up the Charger proprietary end and see which two pins are in use on its’ pins.)

Anyways though I’d elaborate to encourage anyone looking at this thread to try. This is doable! It’s easier than it sounds.

Thanks so much for figuring this out CO!!!

My brand new Dexcon green USB cable was loose at the receiver end right out of the box new. I plugged in the green USB cable into the receiver and it always become disconnected right-a-way. The green Dexcom USB cable is a “3-foot USB-A to Micro-USB Cable”. I have a small cell phone that takes a similar cable. It uses an AT&T “USB-A to Micro-USB Braided 4-foot Cable”. It worked perfectly with a tight positive receiver connection fit. The 1-foot extra length cable is wonderful. This product is compatible with Dexcom CGM Receivers.

Welcome to TuD, @Rudy. That was resourceful of you to find another cable that works. I suggest that you call Dexcom to get a replacement cable for the one that doesn’t work.

Dollar store - one dollar -

Or most smartphone charging cables

I’m planning on it Tony24.