This post is copied from my own thread in padfoneclub.com so there is no case of stealing
If you want to copy this post on other forums please do not forget to give due credits to original poster.
Disclaimer! The procedure described below has the potential of rendering your phone useless if not followed properly. I DO NOT ACCEPT ANY RESPONSIBILITY WHAT SO EVER, IF YOU BRICKED YOUR PHONE WHILE PERFORMING THIS PROCEDURE. PROCEED AT OWN RISK!
This method is tested by downgrading firmware 126.96.36.199 to 188.8.131.52, which in turn needs a factory reset/ wipe data/ cache/ afterwards. Before anything else back up your important data (ie. contacts, messages, app data, etc) to some place safe outside your phone. ORIGINAL RECOVERY of your phone will be replaced by TWRP recovery
Preparation: (BEFORE ANYTHING REMOVE YOUR SIM CARD AND MICRO SD)
1. You must have USB debugging enabled, allow mock locations (developer options menu in settings)
2. You must have UNKNOWN SOURCES enabled (security menu in settings)
3. To be on the safe side I recommend you disable VERIFY APPS OVER USB, in developer options menu. You can re enable everything after the job is done.
4. You need to download firmware 184.108.40.206, and 220.127.116.11 according to your phone SKU and save it on your computer.
5. Download WINRAR or any archiving software which is able to modify zip files and install it on your computer.
6. Download unofficial TWRP ver 18.104.22.168 ONLY from this link
, and save to your computer
7. Download BETA SUPER SU 2.49 from here
, and save it to your computer.
8. If you are on firmware, 22.214.171.124, or 126.96.36.199 and rooted you are half way done, if not either you have to upgrade or downgrade depending on the firmware that now you are on. For example if you already upgraded to 188.8.131.52 you need to downgrade first and root, then proceed. There's a thread in padfoneclub which comprehensively discusses way to root Kit Kat firmware so I skip to just explaining downgrade procedure from 184.108.40.206.
9. To downgrade from 220.127.116.11 to 18.104.22.168, you do it in the usual way from recovery except you need to factory reset/wipe data/ wipe cache via recovery beforehand. REMEMBER TO REMOVE YOUR MICRO SD FIRST AND THEN WIPE OR YOU MAY LOSE YOUR DATA ON MICRO SD AS WELL! After wipe, reboot your phone and place the 22.214.171.124 zip in the root of your sd card by transferring downloaded zip from your PC.
10. Downgrade by choosing "apply update from sd card menu item" in recovery and selecting the zip file you just transferred to your phone. Remember to have at least 70% charge on your battery before downgrade or upgrade.
11. After the downgrade process completes your phone reboots, if it is stuck in ASUS logo for a long time (more than 10 min), switch off your phone by pressing and holding power button. Then reboot into recovery again do another factory reset / wipe data / wipe cache and reboot again. Now everything will be OK and your phone boots to initial KK setup. proceed until you are on the home screen. reboot your phone again.
12. make sure that items explained in step 1-3 are checked and unchecked accordingly.
13. Root your phone by your desired method.
NOW THE IMPORTANT STEPS TO UPGRADE TO A ROOTED ANDROID L 126.96.36.199
1. On your PC replace the "recovery.img" in the zip file for Firmware 188.8.131.52 with TWRP recovery that you just downloaded. Both have the same name and it is a simple case of drag and drop into zip file.
2. Now you have 3 important file:
- The modified 184.108.40.206
- The TWRP recovery you downloaded (recovery.img)
- The beta Super SU 2.49
Copy all 3 file to the root of your sd card in your phone.
3. Install "Terminal Emulator" from Play Store, open the terminal and give it root permissions if needed.
4. Type su
5. Then type
dd if=/sdcard/recovery.img of=/dev/block/platform/msm_sdcc.1/by-name/recovery bs=4096; sync;
(you can copy paste to rule out any typing mistake)
6. After executing the command a number of bytes transfers and the results will display in terminal window. close the window and reboot into recovery as usual, except this time you have TWRP recovery instead of original Asus recovery.
7. Go to "Install" button and select the modified 220.127.116.11 from your sdcard, uncheck "zip file signature verification" then "add more zips" and select beta super su 2.49. zip as well, then swipe to confirm flash.
8. If everything goes according to plan your phone will be flashed with the new firmware and rooted at the same time.
9. Reboot and enjoy!
10. I tried this method on my phone and it all went smoothly, but in case you get errors, you have to figure it out yourself, I WONT BE ABLE TO HELP YOU! AGAIN BE CAUTIOUS, FOLLOW STEPS EXACTLY AS DESCRIBED AND PROCEED AT OWN RISK.