4S diagnosis help, please? (experienced insight ONLY, PLEASE)

[uid15]

Hey there.

I have a 4S which I got from eBay. Ok, first off, I would like to mention that I am a qualified electronic service engineer, so I know what I am doing with electronics and assembley/repair procedures etc, BUT... I am looking to find the symptoms of common issues BEFORE I chase my tail and lose my patience (which is not easy to do for me).

#1 Bought used 4S from eBay - battery cycle count 960+, and dying within a few hours, from 100% (purportedly, and sometimes and instantaneous drop from ~20% ish to immediate shutdown)

#2 Bought a GENUINE battery from a local company (http://appleipodparts.com) - I know these people, they are 4 miles from me, and they are mutual friends of an industry contact, also 4 miles from me, and the battery came with ONE charge cycle logged (they test all their batteries by cycling once).

#3 Tested the new battery in the following manner - it came @ 16% charge, and I only had time to charge it to 65%, and then had to go out. It dropped to 10% in LESS THAN AN HOUR AND A HALF, and then shutdown at 2%.

Whilst the battery was charging, the back of the phone was warm (not hot, WARM) as is usual. During usage, the back was slighltly less warm then when it was charging, but was noticeably warm, nonetheless.

I understand that the ion bonds need to form (?) and that the battery charge retention will increase the more I charge it, but this rapid a drop from 65% to nothing, in SUCH a short time, seems pathetic. I have examined this 4S internally, meticulously, with a magnifying loupe, there is NO internal OR external water damage (dock sensor is tripped red, but that is very common) - headphone sensor is still WHITE, as are the internal sensors.

Is there anything obvious I am missing? 3G data and location services were both ON during my initial test. This thing is starting to annoy me now, it's through common sense and clear thinking that it hasn't yet met a high speed hammer...

Many thanks, if you are able to point me to CLEAR, KNOWN symptoms (and you are of engineering ilk, and not just some random bod breezing by throwing guesses at me) it would be very much appreciated.

Remember, before trying to help, PLEASE DO NOT GUESS when offering advice - I can guess things myself, as an engineer, I am asking for service advice from experienced iPhone service people, thank you

Thanks everyone have a great weekend.

 

[nox5]

Based on my experience battery tends to discharge quickly right after restoring iOS and all the apps. The iPhone is warmer for about a day but everything returns to normal after day or 2.

Also there could be some corrosion under those large chips. After all The iPhone is old and even humid air can do damage after so many years.
Somtimes little heat can help.

 

[uid15]

Based on my experience battery tends to discharge quickly right after restoring iOS and all the apps. The iPhone is warmer for about a day but everything returns to normal after day or 2.

Also there could be some corrosion under those large chips. After all The iPhone is old and even humid air can do damage after so many years.
Somtimes little heat can help.

Indeed humid air can do that, but it doesn't get too humid here in the UK, LOL! Too cold for that

There's zero sign of any form of moisture, at ALL. Here's a weird thing... the first charge of the new battery took HOURS to charge up by few battery percentage points (the climb from 38% to 42% was about an hour!)... but now... it's gone from dead to 72% in just over an hour... AND... it's now COLD when charging... Weirdddddddddd


any ideas? thanks

 

[eicca]

I'm sure you've thought of the possibility of a defective battery (it happens, no matter the source). But I'll throw it out there again.

My next step would be to send that battery back, put in another new one and if that doesn't fix it, there's a problem elsewhere. DFU restore just to be safe, but at that point in the diagnosis it would likely be a bigger problem elsewhere in the phone, and would be best just to get a new phone.

 

[uid15]

I'm sure you've thought of the possibility of a defective battery (it happens, no matter the source). But I'll throw it out there again.

My next step would be to send that battery back, put in another new one and if that doesn't fix it, there's a problem elsewhere. DFU restore just to be safe, but at that point in the diagnosis it would likely be a bigger problem elsewhere in the phone, and would be best just to get a new phone.

~ The 4S had the same drain issue BEFORE the new battery was installed (I did it today), so the chance of the battery being faulty is possible, yes, but HIGHLY improbable - I am speaking from 24 years of engineering experience across a wide range of devices.

~ It's still charging now, has reached 88% capacity, and is charging MUCH faster than earlier... and is not warm AT ALL, unlike earlier today (and before the new battery).

~ I'll wait until it hits 100% full, do a backup and DFU fresh iOS 8.3, then restore my backup and check it for a few hours.

You say "just get a new phone"... yes, but they cost money, and if I had money to splash about, I'd not be using a 4S, let me tell you

Many thanks for the advice, it's appreciated a LOT.

 

[eicca]

Like mentioned, it's very likely the phone just had to calibrate to a new battery. Mine was used to a 500-cycle battery and I still had to DFU restore to blast its memory, I can only imagine what it must be thinking after living with a 900-cycle battery. Give it some time, hopefully that will save you having to spend more dough.

 

[uid15]

Like mentioned, it's very likely the phone just had to calibrate to a new battery. Mine was used to a 500-cycle battery and I still had to DFU restore to blast its memory, I can only imagine what it must be thinking after living with a 900-cycle battery. Give it some time, hopefully that will save you having to spend more dough.

Yes, I'll try that. I want to get a 5S at some point, but for now, this will suffice. I guess that's what happens when you get iPhones from eBay "traders" who promise the universe and then deliver a square quarter acre of polluted soil...

 

[nox5]

based on IMEI how old is the iphone exactly? you can check estimated purchase date here:http://www.iphoneox.com/

 

[uid15]

based on IMEI how old is the iphone exactly? you can check estimated purchase date here:http://www.iphoneox.com/

June the 13th, 2012 (approx). Not sure why that matters

 

[nox5]

June the 13th, 2012 (approx). Not sure why that matters

well on average iphones have 300 charging cycles per 1 year and yours has 900 cycles after 3 years. That suggests the iphone had no issues until late when battery finally failed. So that motherboard may be perfectly fine and just some code that manages the battery needs to be cleared by itself.

Sometimes iphones can act strange. You just need to use it and see if battery life improves later.

 

[uid15]

well on average iphones have 300 charging cycles per 1 year and yours has 900 cycles after 3 years. That suggests the iphone had no issues until late when battery finally failed. So that motherboard may be perfectly fine and just some code that manages the battery needs to be cleared by itself.

Sometimes iphones can act strange. You just need to use it and see if battery life improves later.

Yes, that makes sense to my logical mind

I've DFU restored 8.3 fresh, and restored from a backup; I'll let you know the outcome soon. Many thanks all

 

[BittenApple]

Why don't you do a clean install and test it out like that to see if its a software issue or not. It might be some corrupted settings that you are inheriting from your backup.

 

[uid15]

Why don't you do a clean install and test it out like that to see if its a software issue or not. It might be some corrupted settings that you are inheriting from your backup.

Might not be a bad idea actually. I've been testing it for the last 24hrs with DFU fresh 8.3 and backup restore - it's MARGINALLY better, but just a moment ago, it shutdown @ 20%... VERY annoying. I may just have to try your idea, that makes a lot of sense indeed.

[EDIT]

I've just backed up, and I am now trying a FRESH, CLEAN iOS 8.3 for 24 hours