Experience with damaged NAND-chip in iPhone 4 - GSM-Forum

jegerjon · 05-14-2013, 20:44

Hello friends.

A costomer brought me an iPhone 4 with the description "it is acting weird". He told me that he bought it on e.b.a.y so thinking it is probably just some water damage i began inspecting the board. I quickly found some missing components, but also saw some solder residues arond the EMI shield for the PMIC and NAND. After desoldering the shield, I realize why the phone "is acting weird". Lol, take a look:

I have never seen anything like this (well, except from PMIC's

)!

So first question: what in earth could have caused this sort of damage???

Second question: in order to replace the NAND chip (which contain serial number, right?) I need to have matching BB-cpu and BB NOR flash, is this correct?
I have reballed the NAND-chip once before, but never changed it so my knowledge on this area is limited.

Third and last question: if yes to number two, then I actually have a spare board with these three chips, but what are the chances of the phone actually working afterwards? Based on the picture, would you say the board/track or maybe the A4 CPU (located right on the opposite side) are damaged?

I would love some feedback from some experienced technicians.

Thank you!
Jon.

dog68 · 05-14-2013, 21:37

I would leave it alone, it actually looks like its been microwaved! its almost certain that the cpu has died.

jegerjon · 05-15-2013, 11:55

Uhm, a microwaved board. That is a first...

I will return the board and tell that it is damaged beyond repair. Thank you for your input.

05-14-2013, 20:44	#1 (permalink)
jegerjon Freak Poster Join Date: Nov 2012 Location: Denmark Posts: 172 Member: 1839857 Status: Offline Thanks Meter: 46	Experience with damaged NAND-chip in iPhone 4 Hello friends. A costomer brought me an iPhone 4 with the description "it is acting weird". He told me that he bought it on e.b.a.y so thinking it is probably just some water damage i began inspecting the board. I quickly found some missing components, but also saw some solder residues arond the EMI shield for the PMIC and NAND. After desoldering the shield, I realize why the phone "is acting weird". Lol, take a look: I have never seen anything like this (well, except from PMIC's )! So first question: what in earth could have caused this sort of damage??? Second question: in order to replace the NAND chip (which contain serial number, right?) I need to have matching BB-cpu and BB NOR flash, is this correct? I have reballed the NAND-chip once before, but never changed it so my knowledge on this area is limited. Third and last question: if yes to number two, then I actually have a spare board with these three chips, but what are the chances of the phone actually working afterwards? Based on the picture, would you say the board/track or maybe the A4 CPU (located right on the opposite side) are damaged? I would love some feedback from some experienced technicians. Thank you! Jon.

05-14-2013, 21:37	#2 (permalink)
dog68 No Life Poster Join Date: Mar 2012 Location: cambridgeshire, England Age: 55 Posts: 760 Member: 1728699 Status: Offline Thanks Meter: 212	I would leave it alone, it actually looks like its been microwaved! its almost certain that the cpu has died.

05-15-2013, 11:55	#3 (permalink)
jegerjon Freak Poster Join Date: Nov 2012 Location: Denmark Posts: 172 Member: 1839857 Status: Offline Thanks Meter: 46	Uhm, a microwaved board. That is a first... I will return the board and tell that it is damaged beyond repair. Thank you for your input.