I experienced a problem with my Keurig K-Mini Coffee Maker wherein it would intermittently work upon closing the lid. The LED lights would flash and the unit either stop the brewing process, or not start at all. Working the lid up and down several times would tend to get it working again. Looking for the root cause I observed a small ribbon cable that connects the top of lid the coffee maker internals. Fiddling with this would reproduce the problem, indicating a bad connection as the likely culprit. Eventually it stopped working all-together.
Pulling it apart the cable was clearly damaged. I'm not sure if this was due to wear-and-tear over the years, or an unfortunate
placement of the cable over the lid hinge which would stress the cable each time the lid was actuated. Rather than throwing the coffee maker out I decided to see if I could get a replacement ribbon cable. Pulling the unit
apart I saw that the ribbon cable was labeled AWM 20624 60V VW-1, with 10 pins and a 0.5 pitch.
I was able to locate a few of the cables on Ebay, which worked perfectly. If doing this yourself, I'd recommend a length of at least 15 inches which will give you plenty of extra room to route the cable from the lid to the mainboard. About $10 in parts delivered and my Keurig was back in action.
While pulling the unit apart I noticed a four-pin diagnostic port on the bottom of the coffee maker. This port is wired to a larger five-pin header on the main board labeled "ACCESS". That piqued my interest, so I poked around a bit more with the cover off.
The four pin connector indicated a possible serial port.
There is also a ten-pin JTAG header on the mainboard.
Near the JTAG header was a chip marked 845M301 and NXP. A quick internet search revealed this to be an NXP LPC84x family 32-bit
ARM Cortex-M0+ microcontroller. [Data Sheet]
Using a Tigard hardware tool, I poked around to see if I could identify protocols or dump anything via the JTAG port. Unfortunately I did not have success. It's possible these have been disabled from the factory, though more likely beyond my amateur hardware hacking skills for the moment.