[8.9" Kindle Fire HD Q&A, Help & Troubleshooting] DragonFire1024:
My roommate gave me his Kindle 8.9 to play with and root if possible. I had been successful at rooting, flashing TWRP, but couldn't get a custom ROM to flash. Being stupid, I didn't do a test flash first, so I ended up wiping the system and storage, so I couldn't boot into anything aside from TWRP and ADB was unresponsive. It also caused a power error, causing the device to turn back on immediately when powered down.

I acquired two of these tablets from eBay, for $35.00 a Piece, in like-new condition. I replaced the one I broke and bought one for myself. The problem I had was, there is no single guide which 1) lists the current root method for this tablet 2) The files needed to flash a custom recovery once root is gained 3) the most up to date TWRP recovery available. I read a lot of stuff on XDA. I read a lot of stuff elsewhere. The root methods listed in most every thread, no longer root. It was very hard to find an updated TWRP recovery, but thanks to [MENTION=593185]ong14[/MENTION], who pointed me to a single post, that was possible. So, I created this guide as a single go to for the current methods to root, TWRP and install a custom ROM.

***THIS GUIDE WILL ROOT YOUR DEVICE AND INSTALL A CUSTOM RECOVERY FOR THE AMAZON HD 8.9 JEM TABLET ONLY***

This method is used with ADB which requires Windows. Please make sure the proper drivers are installed before performing these steps. Required files for rooting and custom recovery installation are available at the bottom of this post. Please see respective links for custom ROMs. I did not create any of this software or the files. I'm not responsible if your device is damaged or bricked.

1. Enable the installation of files from unknown sources in Settings > security.

2. Enable ADB debugging from Settings > device.

3. Using the Silk Browser, go to Kingroot.net and download, install and run the APK. Also from Silk, download and install Total Commander File manager and grant it root access. Once you do that, download FireFlash11.apk at the bottom of this post. Open Total Commander and navigate to /sdcard > Downloads. Install FireFlash, open it and grant it root access to use later. (You can locate FireFlash from Home > Apps.)

5. Download the rest of the files at the bottom of this post and place into a folder of your choice on your desktop. Then go here and download this file and this file and place them in that same folder. Then move the following files to your Kindle: freedom-boot-8.4.6, u-boot-prod-8.1.4, stack and kfhd8-twrp-3.0.2-2-recovery.img.

5. Please follow the steps below from [MENTION=6537881]MeowDude[/MENTION] which will tell you how to flash a custom recovery to your Kindle.

You should boot back to recovery at this point and do a factory reset. Here is how to do that below:

1. Power off your Kindle.

2. Once off, press first and hold the volume down button, then the power button. Hold them both down until the device boots to the BLUE Kindle logo. Then release the power button then the volume down button.

3. You should see the "Team Win" logo come across the screen. Tap on wipe, advanced, and choose dalvik, data and cache. Ten swipe the wipe button. DO NOT SELECT THE SYSTEM OR INTERNAL STORAGE OPTION. This will do a clean install of FireOS 8.5.1 and get rid of Kingroot.

Installing a custom ROM

You can now use FireOS as you were able to before, but I was unable to get the necessary Gapps to work with each other properly. You can try, but I recommend installing a custom ROM. I've tried two so far and can confirm they both work. I will list the links below where you can get the ROMs and installation instructions.

1. The Candy Rom, based off of Lollipop 5.1.1, works on this tablet. Root is built in so you don't need to install or flash SuperSU, but the post does say you can flash it. I've had a lot of trouble with custom 5.1.1 ROMs when it comes to launchers. Be warned it doesn't play nice with Nova and will cause the SystemUI to crash and restart over and over.

2. Unofficial CyanogenMod (CM 13). I currently use this ROM. Root is also built in. I have had trouble getting used to the permissions for apps. I have to go in and set them myself. If you can't get the Google app to sign you in, go to settings > apps > Google App > permissions > grant all permissions. I cannot get Hangouts to work, but the dialer works perfect. I'm not sure if either of those issues are a fault of mine or just a fluke.

I own 3 Amazon tablets: Amazon Fire 7, rooted with a custom ROM. Amazon Fire HD 8, but unfortunately there's no root for it yet. Amazon Kindle Fire HD 8.9, rooted, custom recovery and ROM. I have had great fun 'hacking' these things. I hate FireOS, but I will give Amazon credit for making some really bad ass tablets.