NAND corrupted, this is the same issue like others. the so called mobo problem is actually NAND corrupted. there is 1 user from XDA saying something in jelly bean 4.1.1 could be altered something in NAND sector writing, so when you use your phone to a very low power stage (15% or lower), then the i9300 jelly bean 4.1.1 will start to write to certain area of NAND where it shouldnt. after that, apps/phone start to crash and slow response, then after reboot it may be dead.

other user in chinese forum said that SC told them is MMC problem, MMC maybe refer to the internal NAND.


so there are chances that phone will die in half-brick mode, so anybody that root/flash should always use triangle away to play safe, although most of the users reported samsung never check the binary counter.



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and last, all my replied are not official or any statement from samsung, if anybody think this is not appropriate or not helping, click report or reply or pm me, and i will stop and delete all my post.

This post has been edited by JC_jun: Dec 10 2012, 02:36 PM

good that you can contribute some effort to understand the issue.

what is your current rom version? jelly bean 4.1.1 on DLJ1?
try to charge with samsung ori charger.

do nandroid backup regularly and export a copy to computer

in case if you lucky/unlucky to get your board fried, you can get replacement board and be worry free for future. unlike me, i own first batch but not dare to fry the phone until i get myself nexus 4. once i my new phone next year, i will try to fry it.

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Added on December 10, 2012, 2:57 pmno, root or stock totally irrelevant to the motherboard issue. cases were reported from phones running stock, or custom rom, or aosp rom, stock kernel or 3rd party kernel with under clock, under volt, over clock. so this is totally random but at least can narrow down to first batch.

This post has been edited by JC_jun: Dec 10 2012, 02:57 PM

no, warranty will remain. when they change the board, they will re-flash the board with your IMEI and Serial number, so next time when you walk in to service center, they will search your IMEI for warranty status.

the problem is how many others out there who got problem but dont know to report to forum. just count here, for the last few weeks almost every 1 or 2 days there will be victim reporting in. quite serious. only samsung has the statistic of this problem.

for product with "batch" problem, problem board maybe only hit the early batch, so the next batch or after may not be worried because new board, so when the phone keep selling, it will make the failure rate to show smaller and insignificant.

for new owner almost can be worry free, but first batch user still need to keep finger crossed.

nobody can be sure what is the root cause, so try to gather something in common among the problem unit. if you check last few weeks there were a lot users complain that they encountered charging issue with original samsung charger, and samsung SC exchanged charger for them and charging issue resolved immediately.

maybe it is unlikely to be charger problem, but still if you want to minimize the risk of getting mobo fried, try avoid.

i believe you know this flash rom thing very well, in this case most likely is the NAND corrupted. similar to multiple reported case in other forum, go SC and get a motherboard replacement. there were 2 cases i read in cari forum got replacement successfully.

try 1 thing, boot into download mode, and see what is says about your phone model and part number. if it is empty, then no need to waste effort to flash, get replacement asap.

every hard to tell whether they replaced or not, unless you noted down all these hardware info.
my friend has this signal issue, but according to him if using earphone everything works fine, but if use the phone to talk directly you might experience something like audio breaking problem or signal problem. i helped him to flash the phone with other modem and waiting him to test out.

if you still not comfortable with the first batch board, go ahead and try to do warranty claim again. this is your right and this is also the only reason you purchased SME set. utilize the warranty service.

from previous thread and experience from other forumer, SC just downgrade their phone to ICS and told them jelly bean not stable at the moment. so you need to make up some story to make it really look like the board failure to convince them to get a replacement for you.

if you feel comfortable with this first batch board, you can try wipe data/cache of the phone or even flash it with other rom and test if the problem persist. this is very risky, you may brick you phone, so think twice and think wise before taking any action.

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Added on December 12, 2012, 2:03 pmcheck this, somebody recovered pit file by flashing 3rd party thingy..
http://forum.xda-developers.com/showthread...1993044&page=17

but doing this will increase your binary counter and SC might tell you your warranty voided.

you need to make your decision.


This post has been edited by JC_jun: Dec 12 2012, 02:03 PM