iPhone 3gs, what chip is damaged?
 

i have an iPhone 3gs that no longer charges or syncs. It will still work with dock port accessories such as an FM transmitter. If turned off and connected to its usb cable (wall charger OR computer) it will turn itself on everytime. If turned off it will "trickle charge" very very slowly, approx 50% in 24 hrs.

This happened after a specific incident. The iPhone was plugged into an iMac's firewire port with a usb adaptor. Nothing seemed to happen, and afterwards an external hard drive was tried, and nothing seemed to happen. so everything was reconnecred via its normal USB ports but neither device was recognized any more. evidently the usb controller board for hard drive was fried and something of the iPhone's was too.

So what needs to be replaced?
my own research leads me to believe either the pmb6820 or the ltc4088-2.

What do you all say on it? where should i proceed?

78 views and no comments.

if i DID find out which IC to replace, are they need soldered or reflowed?

first thing check fuse, yesterday had same problem after car charger

br

hey thanx for response. really.

anyway, fuse? what fuse? or more importantly...where? ive never noticed one anywhere in any of these phones before.

NOW, two things you must do first

1- change your battery
2- change usb flex
3- check the following on the pic

http://img245.imageshack.us/img245/4735/charging3gs.jpg



Powered by **** team
br
Alex

have already changed flex cable. in fact i changed the entire dock port assembly this afternoon and no change.

how do i check the fuse?
visually, or with a multimeter?

you have to check with multimeter but id you dont have one just make a link in the charging fuse

no i have a multi meter. so all i need then is a continuity check right?
i'm gonnna go get it now.

assuming the fuse IS ****n, do i just solder the gap or is replaceable?

just solder a link, bare in mind no more protection after ;)

much thanx. i'm going to get to work on this and then i'll report back

http://img408.imageshack.us/img408/2...g3gspinout.jpg

Uploaded with ImageShack.us

ok it looked like you wanted me to test the poles that i re-labeled with numbers. i wasnt sure if it was 2 fuses or the 2 legs of a fuse on the other side. anyway in ANY configuration all labeled poles showed continutity.

the green fuse near vibrator also showed continuity.

are the 2 smaller items near what i labeled related? because they had different readings which i won't list unless it matter

OK just change your battery then....they are cheap ;)

i didn't remove the board for testing i just left it screwed into its housing. (just thought i should mention. don't see how would make a difference but just in case...)

anyway, you really think its the battery?
i only ask because the phone WILL turn on and function perfectly minus the fact it won't sync via cable or even be recognized. i would think syncing and battery would be unrelated, no? and secondly, if the phone is turned off and left on the wall charger it will gain SOME charge, very slowly. maybe 30% in 24 hours.

but just to clarify the phone doesn't ever acknowledge that its receiving any current, meaning no beep, or batt icon change. although if turned off and put on the charger it will turn itself on. but thats it.

Ok no worries

I want you to do this, "see in the pic you marked 1,2,3,4 i want you to link(short circuit 1 and 2

it allows you to plug in a usb cable to a firewire port. ...or in theory. i think it was ACTUALLY meant to plug in a firewire DEVICE to a usb port. there was non documentation with the product so i figured this must be what it was intended for AFTER the fact. so voltage from the computers firewire port went somewhere it shouldnt in the iphone.

just to clarify, ok so solder 1 to 2 or use a jumper wire right to link them right?

yes just use a wire and link them

that was harder than it sounded. still no sync or charge

http://img443.imageshack.us/img443/7...ingproblem.jpg

This SOLUTION been posted by other member, I haven personally tested because I never had the need to.

This is serious hardware work and you must at your own risk.

just to make sure, i tried it powered on and plugged in to computer to check for sync or charge while making sure i had an absolutly strong jumper connection and while nothing happened, when i pulled the probe out of the vase it shorted for a tiny second against metal bezel (ground) and the computer gave me a notice i was drawing too much power. so its very obvious that juice is flowing at least up until that point.

i'm not sure i understand whats happening in the diagram or what it attempts to achieve.

and that pic is a 3gs correct?

also is there a proper way to remove the aluminum that covers up that area of the phone?

First of all, just replace another battery with GENUINE 3Gs battery (i repeat a GENUINE 3Gs battery) most likely will fixed your problem.

to remove the shield, you just need some sort of a small flat head screw driver or a guitar spectrum.

the above picture is correct for 3Gs USB docking filter, if you cannot find the replacement filters then do the link as shown the above picture.

Good luck!!

Yes, I suggested to replaced the battery before getting deep into hardware
It's much safer also for a nubie.

i'm not trying to dispute you on the battery issue, but have you read my original post in full?
there's much reason to believe its not the battery. if after reading it in full, if you still feel the same way about the battery please let me know.

what do the docking filters do?

The filter protect the phone for wrong polarity and over-voltage and mainly filter interference and supress voltage spicks(also sometimes cause by statick energy diference between units) cause by other devaices when you plug into the phone(like charger, computer,back batery etc etc)

Yes the BATTERY also has a over-voltage and over-current and smart power managment circut built in

So i would try another battery as a precaucion

I still recommend you to check or replace the battery first. and those FUSES and FILTERS from the above memtion posts. IF still o result, then those 2 ICs in the attach picture, i will replace them.

that's all

good luckhttp://img96.imageshack.us/img96/775...phonefront.jpg

i don't mind getting into the hardware, i'm only a newbie to the internals of the iphone, not electronics. i don't really understand the inner workings of the iphone completely. just its basics from exploring and reading any tidbits i could find. thats why my own amateur diagnosis was the usb ic chip. but since its reacts to things plugged into the usb i'm not so sure. anyway thats how i stumbled onto this site. people seem very knowledgeable here

i'm no stranger to soldering circuit boards, or swapping out known defective components on such things as audio amplifier boards, or fixing electrical connections large and small.

no offense taken though! :D

i just need guidance as where to concentrate while looking for a solution or bad component. i am very appreciative for any and all help. especially thanx to alexlaboratory. you've been working hard to help me. thank you again!

thank you for the explanation, now that i know what they do, since you both strongly believe it could still be the battery, i will try that first.

the idea of bypassing a fuse doesn't seem as bad to me as bypassing the filters. that seems more of a last resort.

@ mphone: yes, i checked the fuses already. i am thinking of checking the one on the battery itself too? waste of time?? (if you read my original post you will see it does "un officially trickle charge", which tells me current is reaching it, but is mostly weak from bad connection or some kind of incurred resistance somewhere)

Your reasoning is correct, and the filters could be the answer..........but please check battery and change if possible.

It a must to check that Fuse as well.

thanks

i will obtain the battery which will probly take a few days, then report back here wether it worked or not.

if not, i will ask for help with the filters.
was that diagram for bypassing the filters by some means?
if it turns out to be one of the ICs, those require a special equipment to change, correct?

yes you gonna need hot-air station

the new genuine 3gs battery came in today. replacing it, did not solve the problem.

oddly, when the screen is turned on, the phone will randomly reboot itself. this is new since replacing the battery. i dont know if this indicates anything, if something is loose, or just coincidence.

what do i do next?

Did you try Resore the phone yet? try put in in dfu mode see if the computer detects it...............

no i havent, because the phone isn't recognized on the cable. i will try DFU mode and see if it is detected.

i believe its hold power and home until apple appears and then release power?
removing the logic board will take it OUT of DFU mode if that fails correct?

with usb in hold pow+home button for 10 secs then realsease pow and keep holding home button

no luck. still won't recognize phone.

i swapped the old battery back in, and it stopped rebooting at random. wierd.



anyway, so what should be the next step?

next step remove and link those filters in the picture i posted before

sir i have 3 i phone 3gs 16 gb,,...
my phone is shorted after over charging...my phone is dead
plz help me

have you done this before?
do you break them off, or use a soldering gun (solder iron)?

most circuit boards i worked with, you can melt from the bottom, but you cannot do this with an iphone board. so i am asking questions or tips before i start to prevent damage

you should use hot air station to desolder them with out damage to the component or pcd

yes you could break them off but bit riscky and doggy way to do it, lol:rolleyes:

i was afraid that would be the answer. i have no hot air station, only gun.

maybe this is where i stop....

if i can find someone with a hot air station, is it possible to purchase the usb control IC and the power ic?

I have a 3gs turns on fine when plug in to the charger . I restore it with the computer the iphone had suffer water damage. And it give me error 23 and now stuck in itunes mode. could the problem be the filters?

http://img153.imageshack.us/img153/7...ingproblem.jpg

The parts that have been removed in the above image are not 'filters' (presumably people mean inductors?). They are MOSFETs (P-channel transistors) Si8409DB, designated Q4 and Q5 on the circuit. The datasheet for the MOSFETs is: http://www.vishay.com/docs/73111/73111.pdf and will show that the devices have 4 bumps using lead-free solder. The bodge above would most likely be linking the source and gate pads judging by the datasheet. This would provide VBUS and VBUS_PROTECT with full USB voltage.

Whoever came up with this certainly knows their stuff. Who did come up with the workaround?

My 3GS had the battery fail. I bought another and fitted it, but although it runs the phone, it won't charge. Sometimes it'll show the battery charged icon (plug), other times the lightning symbol (or the lightning symbol if you unplug and replug enough times). Either way, when it shows it's charging, it isn't actually charging, and the battery is depleting very quickly compared to normal.

i need to change ic chip for iphone that have no baseband. The bord are damege by puting ipad baseband 3gs. Flexqueen sell these to chage ic chip has anyone buy these?
LK863 Professional Infrared Repair Station with Soldering and Hot Air Gun
Who changes these chip and how?? i will send 2 bords to get them fix anyone???
[email protected]

Need some advice
 

Whilst I realise this is an old thread and I don't normally revive old threads, this is the best thread I've found yet that comes closest to my problem and gives real fixes.

My partner fried his iPhone 3GS by trying to connect a faulty charger straight to the car battery (yes, he was drunk at the time, you'd have to be to think that was a good idea wouldn't you?). Anyway, at the time it appeared to be ok but then we found that although it said it was charging, icon came on, phone made the noise when it was plugged in, it actually wouldn't take a charge. We tried buying a new battery and swapping with my battery but neither would charge in his phone though they were both fine in mine.

We got the phone replaced on insurance and it sat in pieces for a few months. We then put his brother's motherboard in his phone primarily because the screen was smashed but it was in pretty bad condition with buttons missing etc.

I recently decided to see if I could rebuild the phone for my daughter. I have replaced nearly everything in the phone, all buttons, flex cables, (wifi cable still to arrive), charging dock, literally everything. The phone works, much to my amazement and the excitement of my daughter. However it still charges slowly. It does at least take a charge but can take as long as 24 hrs to fully charge. It initially lost it's charge extremely quickly even when not in use, however usage time has appeared to increase after a few cycles.

So, logic tells me that obviously the problem is on the motherboard. My suspects are of course the fuses (hopefully) or an IC. My question then is how do I test them exactly and what is your opinion on the most likely cause of the problem? And where is the best place to source these products? I've looked for IC's but they seem rather expensive and I have only found them on Alibaba and I haven't seen the fuses.

Any help, ideas, suggestions would be appreciated. I'd like to avoid breaking it while trying to fix it if possible and I don't want to spend a whole heap of money on it if it can be avoided. If it is more cost effective I will buy a broken phone and use it for parts.

A few extra things that might help. The phone is not overheating when charging. It also will charge on the wall charger only, it will not charge plugged into the computer. It is detected by the computer and shows that it is charging but it either isn't letting through enough voltage or the battery is draining faster than the computer can charge it. Possibly the cause of the slow charge from the wall charger. I'm thinking, if it's draining quickly due to a short circuit somewhere that would have the result of appearing to charge slowly. Although battery life has improved after a few cycles it still discharges quicker than it should.

Similiar issue. I have a 3gs and replaced the dock connector due to a bad speaker. Now it won't charge with either dock connector, new or old. The battery fuse and charging fuses show continuity, these here:

http://guide-images.ifixit.net/igi/6yvrTqhFHxS4EIHZ

My voltmeter is a centech 90899 and shows "1" before touching anything, then when I touch the leads on the meter together, it blinks, which did the same when I touched the fuses. Those are the smallest fuses I've ever seen. I don't think my battery is bad, because it has always worked, it was just a bad speaker I had and that's why I replaced the dock connector, now no charging on either dock. I did just test the battery too, and the voltage is reading 3.77v, so looks like battery is ok. Would this fix work in my situation? And can I do it with a normal soder gun.

Iphone 3gs 16gb
 

Hi, I was wondering if someone could possibly help me? I have recently started fixing iphones as a little hobbie, ive been given an iphone 3gs by one of my mates, he dropped it and it hasnt worked since, the screen was coming away from the casing and the volume and mute button are damaged. I stripped the phone apart and cant really see any major damage to the insides of the phone. I also own an iphone 3gs 16gb so i tried his motherboard in my phone and it doesnt seem to power up. I cant see no immediate damage to the motherboard in comparison to mine, Any ideas on what the issue could be or how i could go about fixing it? hes not a 100% if there is any water damage but i cant see any rust/corrison on the motherboard.

Thanks:):)