In this thread I would like to consolidate information about eMMC flash memory failures and remedies.
When flash memory fails it becomes inaccessible or unwriteable with errors like the following:
sending 'bootloader' <3911 KB>... OKAY [ 0.202s ] writing 'bootloader'... FAILED <remote: flash write failure> or E:can't mount /cache/recovery/last_install E:can't open /cache/recovery/last_install E:failed closing /dev/block/platform/msm_sdcc. 1/by-name/misc (I/O error) E:failed to mount /cache (Invalid argument) or E:Unable to find partition size for '/boot' E:Unable to find partition size for '/recovery' E:Unable to find partition size for '/misc' E:Primary block device '/dev/block/platform/msm_sdcc.1/by-name/userdata' for mount point '/data' is not present! E:Unable to mount '/data' E:Unable to recreate /data/media folder. dmesg... mmc0: error -110 whilst initialising MMC card
We observe these hardware failure symptoms:
- device is totally dead
- dead but flashes a few times the white LED next to USB port
- dead but with active USB on PC device list
- works up to fastboot stage or Google logo
- may slowly boot Android sometimes
- intermittently Android does not boot or work at all
#1 - eMMC unrelated
#2 - battery fault is most likely
#3 - catastrophic eMMC failure or GPT/bootloader damage, PC registers a new USB\VID_05C6&PID_9008 device, refer to QPST diagnostics below
#4 - partial eMMC failure or OS error, refer to fastboot diagnostics below
#5 - probably eMMC failure, unlocking and TWRP tests are required - post your logs
#6 - unlikely eMMC fault
If your bricked unit still works in fastboot mode then please do the following tests:
- boot the Nexus in fastboot mode (when off press power+vol.dn)
- connect it to your PC
- on PC run:
fastboot oem gpt-info
fastboot format cache
If you get "partition.size 27852783 KB" then your eMMC chip is from Kingston (very high failure rate).
If the format command freezes at any stage, then the eMMC chip is faulty and needs to be replaced.
The normal format output takes only 1 second and is:
Creating filesystem with parameters: Size: 587202560 Block size: 4096 Blocks per group: 32768 Inodes per group: 7168 Inode size: 256 Journal blocks: 2240 Label: Blocks: 143360 Block groups: 5 Reserved block group size: 39 Created filesystem with 11/35840 inodes and 4616/143360 blocks erasing 'cache'... OKAY [ 0.359s] sending 'cache' (10984 KB)... OKAY [ 0.359s] writing 'cache'... OKAY [ 0.484s] finished. total time: 1.203s
- download "New Qualcomm 2012.rar"
- extract the "fre" folder
- connect your N7 to PC and when asked for a driver point it to the above folder
- download "New_Qualcomm_QPST-2.7.422.zip"
- extract it and run "setup.exe"
- run Start/QPST/MemoryDebugApp.exe
- in Memory Debug keep clicking "Browse" until you see a new COM port
- in Memory Debug click "Get Regions"
- in Memory Debug select and save "CODERAM.BIN"
- upload "CODERAM.BIN" here
- ASUS service - apparently they can now do it for free with paid shipping!
- motherboard replacement - for example this one "pulled from a working unit" for $25
- RIFF JTAG Box - while the box is not cheap it can be used for other devices too (v1 was $109). Optional tool.
- off-circuit eMMC programming and chip replacement - it is difficult and expensive but feasible
- in-circuit Service ROM flashing - after chip replacement or if eMMC is OK but with damaged partition table or bootloader
eMMC chip replacement
- do not replace it with another Kingston
- search for eMMC in FBGA 153 or 169 package
- you can upgrade it to a higher capacity memory
- new high-performance eMMC v5.1 requires updated software, available here
Nexus 7 2013 uses 3 brands of eMMC chips: Kingston, Hynix and Toshiba.
Kingston was initially identified as unreliable in this post a few years ago:
Google Nexus 7 2013 (Asus Razor)
This is bootloader repair package for Google Nexus 7 based on QUALCOMM APQ8064 MCU. Tegra based is not supported !
- GPT is for 32GB chip, hence it's not ticked by default. DO NOT tick it if You have 16GB version
- EFS/CEFS partitions You can tick in case that nothing else works, it's not recommended to try it if You haven't made backup first. In this model, partitions layout is different from all other known Qualcomm devices, hence reading first 512MB for backup wont do any help. Do do proper backup, You have to read 2GB + size (from 0x0000 0000 0000 to 0x0000 9000 0000)
Important ! ! !
- If You have device which hangs on Google logo, and resurrection process hangs at 1%, You'll have to replace the eMMC chip first. Kingston eMMC chips used in these devices oftenly fail and become unwriteable !
Attached Files Asus_Nexus_7.rar (103.60 MB)
The above file is for RIFF JTAG flasher.
My Nexus 7 JTAG collection:
- nexus7 jtag.jpg
- RIFF Box JTAG GettingStarted.pdf
- RIFF Box JTAG Manager Setup v1.56.exe
Please post your Nexus 7 2013 eMMC maker in this thread.
So far I have collected the following reports:
BRICKED Kingston Hynix Toshiba ------------------------------------------- graphdarnell 1 fuser-invent 1 aungmyoswe 1 marc1706 1 micl9 1 consumer61 1* bl4cKz4cK 1 patmann03 1 CWempe 1 purian23 1 NX3 1 ali1234 1 lowridincrew 1 DaWeIII 1 HTC Tytn... 1 jaybea 1 vfrvulcan 1 TechnicsKuzya 2 barbuda 1 Snoob25 1 Dazmatic 1 459below 1 amix 1 hypochondrej 1 WORKING Kingston Hynix Toshiba ------------------------------------------- fuser-invent 1 k23m 2 yosmokinman 2 Tmzdroid 1 graphdarnell 1 2 OrBy 1 mydian 1 quickdraw86 1 micl9 1 tegodwin 1* noahvt 1 Carrick Glen 1* Axel85 1 NTRNSTR 1 *2015 production
To check the chip in working units use this app or dmesg:
Kingston (MMC32G) ----------------- mmc0: new HS200 MMC card at address 0001 mmcblk0: mmc0:0001 MMC32G 28.8 GiB Hynix (HBG4e) ------------- mmc0: new HS200 MMC card at address 0001 mmcblk0: mmc0:0001 HBG4e 29.1 GiB Toshiba (016G92) ---------------- mmcblk0: mmc0:0001 016G92 14.6 GiB
It is not so simple with bricked units but this device is exceptionally easy to disassemble. The chip is on the bottom of the motherboard but unlike the top, it is not covered with any shield (the purple chip).