[noismaster]

Things you will need for a successful jailbreak:

• Kindle Voyage
• USB TTL Serial Cable 1.8V
  
  • I used the FTDI TTL-232RG-VREG1V8-WE (from Farnell for 23€ + shipping)
    
• Thin wire (best 28g…36g)
• Soldering equipment
• Linux PC or Linux Virtual Machine (where you can attach USB devices)
  
  • I used a Ubuntu 14.04 VMWare Virtual machine (no extra drivers were needed)
    
• Kindle jailbreak from here
• KUAL from here

I’ll assume that you will use the TTL-232RG-VREG1V8-WE and Ubuntu 14.04

1. Connect you're kindle to your PC and copy the content of 'kindle-5.4-jailbreak.zip' to the root folder of you're kindle
2. Copy the KUAL-KDK-2.0.azw2 to the kindle documents folder
3. Write down kindles serial nr. ('Home' -> 'Menu' -> 'Setting' -> 'Menu' -> 'Device info')
4. Unconnect your kindle
5. Open the device and remove the battery connection (you can follow these instructions up to step 5)
6. Solder the thin wire to the kindle as shown
   
   
   
7. Now connect the thin wire to the USB TLL Serial Cable.
   
   • If you use the TTL-232RG-VREG1V8-WE USB TTL Serial Cable then connect as:
     
     1. Kindle TX -> USB Serial RX (Yellow)
        
     2. Kindle RX -> USB Serial TX (Orange)
        
     3. Kindle GND -> USB Serial GND (Black)
        
   • If you use other USB to Serial connector you’re on your own
     
8. Connect the USB cable to your PC (if using VM also connect the USB device to the virtual machine)
9. Lets find you're kindle root password (serial number should be without spaces!), open a terminal window and execute
   

   python -c 'import hashlib,sys;print "fiona%s" % hashlib.md5("%s\n" % sys.argv[1]).hexdigest()[13:16]' YOUR_SERIAL_NUMBER

   Should see something like
   

   fionac5f

10. Next you need to find the tty device name linux assigned
    

    sudo dmesg | grep tty

    You should see somethind like this, my tty interface is ttyUSB0
    

    [ 0.000000] console [tty0] enabled
    [ 0.925346] 00:06: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
    [ 0.952802] 00:07: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a 16550A
    [ 103.111933] usb 2-2.1: FTDI USB Serial Device converter now attached to ttyUSB0

11. Now you need to setup minicom
    

    sudo minicom -s

    Select 'Serial port setup' then insert into 'A - Serial device' -> '/dev/ttyUSB0'
    and 'F - Hardware Flow Control' set to 'No'
    
    
    
    Next 'Save setup as dfl' and 'Exit from Minicom'
    
12. Start minicom console
    

    sudo minicom

    You should see somthing like this
    
    
    
13. Now you need to connect you're kindles battery and power up the kindle (you can connect a USB power adapter to charge your kindle)
14. When the kindle is starting you should see some output from your kindle startup in minicom console. You need to stop the autoboot by pressing any key. You must be quick because you have only 1 second delay. If you miss it, you have to restart your kindle.
    

    ...
    sing default environment
    
    In: serial
    Out: serial
    Err: serial
    Quick Memory Test 0x80000000, 0xfff0000
    POST done in 59 ms
    Battery voltage: 4163 mV
    
    Hit any key to stop autoboot: 1

15. If you were successful then run command
    

    bootm 0xE41000

16. On the kinle tap 'Exit' and then 'Reboot or Disable Diags', then 'Exit to login prompt'
    
17. Now you should have a login prompt in mincom type user 'root' and password from above
    
    

    Welcome to Kindle!
    
    kindle login: root
    password: *****

18. Lets create a mount point in /tmp
    

    mkdir /tmp/main

19. Then mount the main file system at that point:
    

    mount /dev/mmcblk0p1 /tmp/main

20. Now you need to edit the root password for the main login
    

    vi /tmp/main/etc/passwd

    On the first line there should be
    
    

    root:!:0:0:root:/:/bin/sh

    delete the ! and save
    
21. Now you can reboot, by typing in 'reboot' and wait for the kindel to boot fully
22. Now you can log in to the main system with username 'root' and password ''
23. You can change the root password by executing
    

    passwd

24. Next we need to apply the jailbreak, by executing the following commands
    

    cd /mnt/us && sh jb.sh

25. Finaly we have to reboot and the jailbreak is complete
    
    

    reboot

26. To test that the jailbreak works open the KUAL from your kindle book list
    
27. Now you can disconnect the kindle from the USB TLL Serial Cable and tape the thin wire and close your Kindle Voyage
    

I hope this step by step guide was useful, let me know if you see any mistakes!

I have successfully installed the LibrarianSync to synchronize my collections between calibre and kindle, if there is interest I can make a guide for that to

Some images & text were copied from the following threads, thank you for your hard work

• https://www.mobileread.com/forums/sho...d.php?t=249869
• https://www.mobileread.com/forums/sho...d.php?t=254400
• https://www.mobileread.com/forums/sho...d.php?t=247480