Dead battery boot loop -Poxy Samsung rubbish !

[miffed]

Was just playing a game on my Galaxy S2 , when the screen flickers and the phone dies (while it was supposedly charging via USB ! , I might add ....)

I leave it plugged in, expecting it to recharge , but instead it just does a boot loop - phone is off>> Battery charge screen for two seconds >> phone switches off>> Battery charge screen for 2 seconds .....and so on

Plugging into the mains does the same thing

A Quick Google tells me I now have these choices -

1) Buy a new battery

2) Charge my batter in an External charger (or a "doner" phone)

3) Splice a USB cable up and rewire it , in an effort to bypass Samsungs charging f***ery

4) Throw the phone in the bin

Jesus H Christ ..... I can't believe I am in this postion because I let my battery go flat !

Samsung's only (possble ? ) reprieve here , is that I am running custom firmware *maybe* it's my fault for doing that - I still think its a bit of a crock though :(:mad:

[Ben]

Pop goes the Sammy :(

Could you get it fixed under warranty?

[Wilt]

He should still be under warranty, although sammy might be a bit funny about it due to the custom ROM.

I don't understand how the battery could go flat if it was charging via USB though?

Aren't Li-Ion batteries supposed to prevent themselves from becoming fully discharged to avoid damage like this?

[miffed]

Phew ! Managed to get to to come alive again - I decided to have one last try before ordering a new battery / external charger

I remember reading about a similar thing with HTC devices (although not experienced it with an HTC) where people had managed to boot by warming the battery slightly , I tried this with a hair dryer ..... and lo and behold it worked !

Looks like others haven't been so lucky - http://forum.cyanogenmod.com/topic/36648-galaxy-s2-empty-battery-boot-loop/

Splicing a USB cable and attaching the wires to the battery terminals in the phone seems a bit scary if you ask me ! If you read the link within the link , they are talking about a Moto Droid, so thats Samsung , HTC and Moto ... I wonder whether this is an "android wide" thing ?

Not sure about the warranty - the Bootloader has a "custom binary" counter which notches up whenever you flash a custom ROM on the phone , it is possible to reset using a USB Jig (£2 from ebay) but mine probably reads about 3 at the moment - must get a Jig ! not sure how I would have fared with warranty though TBH , as It was running custom firmware.

I agree , I am not sure how it died either ? I got the "low battery" warning , and plugged it in , it was definitely charging , I can only assume I was drawing more from the battery (playing a game) than the USB charge was putting in ! I know when I charge my iPad via USB it only actually charges when the screen is off ?

Even so , I'd have thought the device would be configured in such a way that it doesn't die beyond recharge ?

[hecatae]

bootloops are down to kernel implementation, if you are running a custom kernel then it's the fault of the custom kernel developer

you can boot and flash a zte on usb power alone, no battery needed

[Hands0n]

What ROM are you running these days Miffed? If its CM7 you could drop a note to the developers, they may tackle it.

[Ben]

How could a boot loop be fixed by warming with a hairdryer if it's a kernel issue?

The thought of miffed sat there hair drying his SGS2 has me quite amused!

[miffed]

LOL - no I remember reading that the heating the battery sightly when dead stirs a little more voltage , and it can be just enough to break the boot loop.
It wasn't a true boot loop where it starts to boot , then resets at a set point - it simply runs out of juice and goes dead during the earliest point of booting (i.e. the battery icon) ... then it seems to muster up enough energy to try again. The more times you let it try, the earlier it cuts out - for some reason the charging circuits just don't "cut in"
I am running custom firmware and a custom kernel, maybe that is the problem ?

[Ben]

D'uh, moment of realisation, this is exactly what my stock Nexus One did. So I don't think it's your firmware/kernel choice at all. Just cheap crap.

I should've looked into it and tried the hairdryer trick; it'll be too far gone now.

[miffed]

Strange , I have had plenty of HTC's (Desire , HD7 , 7 Pro) and not had any trouble ?

I have let the SGS2 "die" before , and it has just booted up again fine when I charged it - it seems that letting it die while under strain (i.e. Playing a game) causes the trouble

Was a real pain in the neck yesterday , but fortunately I was only using it as #2 handset , if I was using it as #1 - or didn't have another phone on me I'd be most annoyed !

An interesting observation is that I started looking out for a customer with an SGS2 so I could "borrow" their battery to try and boot - Didn't see one all afternoon ,about 20 iPhones , 5 blackberries and an Nokia N8 !

[Hands0n]

Li-Ion and Li-Pol batteries have a lowest charge below which they effectively die. They need to be "restarted" by special chargers that send in a high current that ordinary domestic chargers do not. I suspect that heating the battery brings the residual charge in the battery back up sufficient for the domestic charger to do its stuff.

[Ben]

When the iPhone goes completely flat it does that special thing where it shows a flat battery when you start to charge it but doesn't boot up until it has charged back up past a certain point. I think the iPhone is quite conservative with the battery in order to make sure it always shuts off with plenty of juice left to sustain it.

I don't remember ever having to monkey around with a Nokia battery either; even when the phone has been left, quite literally, for years.

Are some of today's smartphone manufacturers lacking a bit of finesse in this department?