T-Mobile G2 Firmware Downgrade (Gingerbread)

This guide will walk you through the process of taking the TMobile G2 from stock Gingerbread firmware to a stock, exploitable version of the Froyo firmware. Once it is downgraded, you would proceed thru the process of getting CyanogenMod on the device. If the TMobile G2 is already running firmware version 1.19.531.1 or lower (Settings » About Phone) you follow the vision install guide.

For other related guides please view the following:

Downgrading to 1.19.531.1

  1. You will need ADB on the computer to proceed thru this process. Follow the Android SDK guide to get the ADB shell on the computer.
  2. Download fre3vo, misc_version 0.2 & the 1.19.531.1 firmware:
    • fre3vo: Download
      md5: 010e076a4a93be876579711bf8934c70
    • misc_version 0.2: Download
      md5: 1f40aaf88d1bf15775631a58c4361218
    • flashgc: Download
      md5: 86e6e81fad3b3c837ed8bd09b6005651
    • 1.19.531.1 firmware: Download
      md5: 531c08dc402e15577b947bf4cd22aec2
  3. Unzip the fre3vo & misc_version packages and save flashgc to the same folder as adb (the /platform-tools folder within the Android SDK folder).
  4. Make sure the filename of the firmware is PC10IMG.zip exactly or it will not work and copy it to the same folder as adb.
  5. Connect the T-Mobile G2 to the computer via USB.
  6. On the computer, open terminal and run the following commands:
    adb push fre3vo /data/local/tmp
    adb push misc_version /data/local/tmp
    adb push flashgc /data/local/tmp
    adb shell
    chmod 777 /data/local/tmp/fre3vo
    chmod 777 /data/local/tmp/misc_version
    chmod 777 /data/local/tmp/flashgc
    /data/local/tmp/fre3vo -debug -start FAA90000 -end FFFFFFFF
    adb shell
  7. You should have the “#” sign instead of the “$”. If you do, you have temporary root, and can continue on. If you have the “$”, then the exploit has failed, refer to xda developers, RootzWiki, or #G2Root for further assistance.
    cd /data/local/tmp
    ./misc_version -s
  8. Now that misc version has been downgraded, the T-Mobile G2 is ready to have the firmware downgraded. On the computer, open terminal and run the following commands:
    adb reboot bootloader
  9. Wait for device to reboot into bootloader mode
    fastboot oem rebootRUU
  10. Wait for a black screen with the HTC logo
    fastboot flash zip PC10IMG.zip
  11. If you see a message saying Failed, repeat this step immediately: fastboot flash zip PC10IMG.zip and it should succeed.
  12. Once finished you can can continue to the next section.

Rooting the TMobile G2

Please follow the vision install guide.

Content of this page is based on informations from wiki.cyanogenmod.org, under CC BY-SA 3.0 licence.