(Volume up) and (Power up): Recovery mode
(Volume down) and (Power up): FTM mode (Field Test mode)
(Volume down) and (Volume up) and (Power up): Download mode
Unbrick your phone.
If you are unable to update the phone via the regular phone recovery mode, adb and fastboot then this is the only method left to try.
Download and install driver.
These tools is only available for windows user. I have tested on windows XP.
Download and install the ZTE USB driver ZTE_Handset_USB_Driver.exe and restart the computer.
This is available from the ZTE website US or EU. (DRV_PKG_ZTE_P752D04V1.0)
Download the 'NandDL for firefox' . There are two file that needed to be place in the same folder
NandDL_firefox.exe
ZTE dropbox download and my local copy version download
ZTE dropbox word file howto instructions. Or you can read my instruction below.
Download ZTE open V1.2 (beta) firmware and unzip it.(ZTE dropbox US version and EU version ) (local download copy)
You need these 'special' V1.2 version or else the update program will not work.
Turn off your phone.
Remove the battery.
Start the download program (NandDL_firefox.exe) and select the folder with V1.2 firmware and select what you want to flash.
push (Volume down) and (Volume up) and at the same time connect the USB cable to the computer.
The phone screen is still blank and all the LED are off.
The screen now show 'ZTE Handset Diagnostic Interface (DFU)'
If there is no text 'ZTE ..' is coming up then try an other USB port.
The press the lower left button and the phone is being updated.
When finish updating, the phone will restart. But it is unstable because there is no battery inside.
- Remove the USB cable.
- Put the battery inside the phone.
- Start up the phone.
Check box selection.
There are more check box available. Not sure if other the files is necessary to unbrick the phone. You can always try enable more check box if these 4 minimum selection example are not working.
There are many partition in ZTE open. Normally you only overwrite 4 partition with fastboot: boot, system, userdata and recovery partition. And the phone goes to bootloop etc. And only these 4 partition need to be restored to get things working again.
Warning:The default recovery mode update via one zip file is user-friendly and is able to overwrite more that the 4 partition describe above at the same time. So be carefully when you download a non-official 'firmware.zip' file. You may not be able to unbrick it if too many partition is modified/change.
root@android:/ # cat /proc/mtd
dev: size erasesize name
mtd0: 00c00000 00020000 'recovery'
mtd1: 00800000 00020000 'boot'
mtd2: 00180000 00020000 'splash'
mtd3: 00080000 00020000 'misc'
mtd4: 03980000 00020000 'cache'
mtd5: 0ea00000 00020000 'system'
mtd6: 09880000 00020000 'userdata'
mtd7: 00100000 00020000 'oem'
mtd8: 00180000 00020000 'persist'
mtd9: 00140000 00020000 'mibib'
mtd10: 000a0000 00020000 'qcsbl'
mtd11: 00140000 00020000 'oemsbl1'
mtd12: 00140000 00020000 'oemsbl2'
mtd13: 01880000 00020000 'amss'
mtd14: 000a0000 00020000 'appsbl'
mtd15: 00140000 00020000 'MIBIB'
mtd16: 00080000 00020000 'SIM_SECURE'
mtd17: 000a0000 00020000 'QCSBL'
After installing the ZTE driver you should be able to see the phone in the device manager under 'Ports'.
If this is not the case then is probably place under 'Other devices'. When this is the case the driver is not installed for this USB port. Select the 'ZTE handset' and with right mouse select 'update driver' from the popup menu. The driver will be installed for this USB port. And the ZTE device will be place under 'Ports'