[Xperia Z Q&A, Help & Troubleshooting] yukin.woo.cn@gmail.com:
Hi guys,

First, please forgive my english is poor.

phone symptoms:

1. Tried press power button, it vibrates but nothing happens, no backlight, no any display;

2. Plug the USB cable charging, red led lights, unplug the USB cable, the red led are still bright;

3. Tried the power + volume up button for 5 seconds, it vibrates once;

4. Tried the power + volume up button for 10 seconds, it vibrates thrice;

5. Hold volume down and plug in USB Cable, it can enter flash mode;

6. Hold volume up and plug in USB Cable, it can enter fastboot mode;

I tried flash stock firmware using flashtool, log show "Flashing finished", but, i hold down the power button it vibrates but nothing happens.

this is flashtool log:

26/011/2015 11:11:14 - INFO - Selected Bundle for Sony Xperia Z (C6602). FW release : 10.5.1.A.0.283. Customization : 1270-9104_CN_shohoku521
26/011/2015 11:11:14 - INFO - Preparing files for flashing
26/012/2015 11:12:47 - INFO - Please connect your device into flashmode.
26/012/2015 11:12:53 - INFO - Device connected in flash mode
26/012/2015 11:12:53 - INFO - Opening device for R/W
26/012/2015 11:12:53 - INFO - Reading device information
26/012/2015 11:12:53 - INFO - Phone ready for flashmode operations.
26/012/2015 11:12:53 - INFO - Current device : L36h - BX903JXF3P - 1270-9104_R11D - 1269-5309_10.5.1.A.0.292 - CHINA-HSPA_10.5.1.A.0.292
26/012/2015 11:12:53 - INFO - Start Flashing
26/012/2015 11:12:54 - INFO - Processing loader.sin
26/012/2015 11:12:54 - INFO - Checking header
26/012/2015 11:12:54 - INFO - Flashing data
26/012/2015 11:12:54 - INFO - Processing of loader.sin finished.
26/012/2015 11:12:54 - INFO - Loader : S1_Root_5ca3 - Version : APQ8064_39 / Boot version : S1_Boot_Lagan_1.1.1_1 / Bootloader status : ROOTABLE
26/012/2015 11:12:54 - INFO - Disabling final data verification check
26/012/2015 11:12:54 - INFO - Processing partition-image.sin
26/012/2015 11:12:54 - INFO - Checking header
26/012/2015 11:12:54 - INFO - Flashing data
26/012/2015 11:12:54 - INFO - Processing of partition-image.sin finished.
26/012/2015 11:12:54 - INFO - Parsing boot delivery
26/012/2015 11:12:54 - INFO - Phone boot version : S1_Boot_Lagan_1.1.1_1. Boot delivery version : S1_Boot_Lagan_1.1.1_1
26/012/2015 11:12:54 - INFO - Boot delivery up to date. Nothing to do
26/012/2015 11:12:54 - INFO - Processing kernel.sin
26/012/2015 11:12:54 - INFO - Checking header
26/012/2015 11:12:54 - INFO - Flashing data
26/012/2015 11:12:55 - INFO - Processing of kernel.sin finished.
26/012/2015 11:12:55 - INFO - Processing rpm.sin
26/012/2015 11:12:55 - INFO - Checking header
26/012/2015 11:12:55 - INFO - Flashing data
26/012/2015 11:12:55 - INFO - Processing of rpm.sin finished.
26/012/2015 11:12:55 - INFO - Processing fotakernel.sin
26/012/2015 11:12:55 - INFO - Checking header
26/012/2015 11:12:55 - INFO - Flashing data
26/012/2015 11:12:56 - INFO - Processing of fotakernel.sin finished.
26/012/2015 11:12:56 - INFO - Processing amss_fs_3.sin
26/012/2015 11:12:56 - INFO - Checking header
26/012/2015 11:12:56 - INFO - Flashing data
26/012/2015 11:12:56 - INFO - Processing of amss_fs_3.sin finished.
26/012/2015 11:12:56 - INFO - Processing amss_fs_2.sin
26/012/2015 11:12:56 - INFO - Checking header
26/012/2015 11:12:56 - INFO - Flashing data
26/012/2015 11:12:56 - INFO - Processing of amss_fs_2.sin finished.
26/012/2015 11:12:56 - INFO - Processing amss_fs_1.sin
26/012/2015 11:12:56 - INFO - Checking header
26/012/2015 11:12:56 - INFO - Flashing data
26/012/2015 11:12:56 - INFO - Processing of amss_fs_1.sin finished.
26/012/2015 11:12:56 - INFO - Processing apps_log.sin
26/012/2015 11:12:56 - INFO - Checking header
26/012/2015 11:12:56 - INFO - Flashing data
26/012/2015 11:12:56 - INFO - Processing of apps_log.sin finished.
26/012/2015 11:12:56 - INFO - Processing cache.sin
26/012/2015 11:12:56 - INFO - Checking header
26/012/2015 11:12:56 - INFO - Flashing data
26/012/2015 11:12:57 - INFO - Processing of cache.sin finished.
26/012/2015 11:12:57 - INFO - Processing system.sin
26/012/2015 11:12:57 - INFO - Checking header
26/012/2015 11:12:57 - INFO - Flashing data
26/014/2015 11:14:59 - INFO - Processing of system.sin finished.
26/014/2015 11:14:59 - INFO - Processing userdata.sin
26/014/2015 11:14:59 - INFO - Checking header
26/014/2015 11:14:59 - INFO - Flashing data
26/015/2015 11:15:10 - INFO - Processing of userdata.sin finished.
26/015/2015 11:15:10 - INFO - Processing elabel-l36h-china_201301211419_10.5.1.A.0.283.sin
26/015/2015 11:15:10 - INFO - Checking header
26/015/2015 11:15:10 - INFO - Flashing data
26/015/2015 11:15:11 - INFO - Processing of elabel-l36h-china_201301211419_10.5.1.A.0.283.sin finished.
26/015/2015 11:15:11 - INFO - Flashing preset1.ta
26/015/2015 11:15:11 - INFO - Custumization reset is now based on UI choice
26/015/2015 11:15:11 - INFO - Flashing cust-reset.ta
26/015/2015 11:15:11 - INFO - Custumization reset is now based on UI choice
26/015/2015 11:15:11 - INFO - Ending flash session
26/015/2015 11:15:11 - INFO - Flashing finished.
26/015/2015 11:15:11 - INFO - Please unplug and start your phone
26/015/2015 11:15:11 - INFO - For flashtool, Unknown Sources and Debugging must be checked in phone settings
26/015/2015 11:15:12 - INFO - Device connected in flash mode

I tried to replace flashtool & firmware version, the same results.

I found a problem, when i use a different version of the flashtool & firmware, flashtool log "Current device" always the same, alway is:

Current device : L36h - BX903JXF3P - 1270-9104_R11D - 1269-5309_10.5.1.A.0.292 - CHINA-HSPA_10.5.1.A.0.292

Looks like the firmware does not burn into the EMMC flash, but i unlock bootloader using flashtool was successful.

I tried erase boot & system using fastboot command:

fastboot.exe erase boot
erasing 'boot'...
OKAY [ 0.018s]
finished. total time: 0.018s

fastboot.exe erase system
erasing 'system'...
OKAY [ 1.367s]
finished. total time: 1.368s

then i trid flashtool to flash firmware, the "Current device" show still same.

please help. Thanks.