Making a Kindle Fire "Factory Cable"

Awhile ago I wrote a post on how to “root” a Kindle Fire without relying on an Android exploit. While a new exploit is being used to allow rooting of devices running the “6.2.1” (+) update, a patch to the OS will likely eventually make rooting more difficult. I’ve rooted my device; in the event I need to root another I decided to make a “factory cable” to root the Kindle Fire.

Factory cable?

In short, think of a “factory cable” in, well, a factory. When your device is being made, the manufacturer plugs in a cable and loads the OS for the first time. They use a special cable which makes the device download a boot-loader with very little fuss. A factory cable allows you to do the exact same thing – it enables someone to load a new boot-loader extremely easily. This can, in turn, be used to load new ROMS (operating systems.)
The directions for building this cable are based on this thread on the XDA forums. Credit with coming up for the idea goes to the people behind that post. This post is a visual how-to.

What’s needed

I wanted something a bit more polished than a paperclip cable so I decided to use this breakout board from Sparkfun.

All-in-all, the parts needed are:

  • The breakout board from Sparkfun
  • A USB cable
  • 1K resistor*
  • Soldering iron
  • Scissors or exacto knife
  • Wire cutters

* A wire can be used in place of a resistor; I used a resistor for safety. Most likely, it doesn’t matter.

Here’s what the breakout board looks like as you receive it from Sparkfun. Pictured with a USB cable.


The process

Step one

Cut the end off of the USB cable. Make sure to cut the end which you’ll be using for the breakout board. Don’t cut the end needed to connect your cable to a computer. Seriously, if you cut the wrong end then just stop now.


Step two

Place the wires from the USB cable and the resistor into the breakout board as follows (labels are from the breakout board.)

  1. VCC – 5V [usually red wire] AND one end of 1k resistor
  2. D- – data (-) [usually white wire]
  3. D+ – data (+) [usually green wire]
  4. ID – second end of 1k resistor
  5. VCC – ground [usually black wire]

This chart shows the breakout visually. The dark grey line connecting the VCC and ID pins is the 1k resistor. If you are using a wire instead of a resistor, the wiring is the same.


Step three

Solder it all together!

Once you are finished, the cable should look something like this from the front. Please excuse the sloppy wire ends – I don’t have the proper wire cutters at the moment.


The cable will look something like this from the back.


Step four

The cable is done! Follow these directions to use the cable.