No boot and battery question

[Alex Johnson3]

Hi guys. I have a samsung focus and it stopped working. Tried charging it but does not work. The OEM splash screen will popup and after that a low battery screen, then it will go black. I tested the voltage on the battery which was around 3.4 volts (it should be around 3.7 nominally). So the battery is obviously not charging anymore. I coonected the phone to an adjustable DC power supply and gave it exactly 3.7 volts. This time when i tried to turn on it would vibrate(as it should) display the OEM splash screen and the go black again. No low battery symbol appeared. This lead me to conclude the phone was screwed. However i only connected positive and negative contacts. Their is a third that i am not sure what it is for. I think it may be used for charge estimation or maybe it is a security feature that will only allow the OS to boot with a samsung battery. SO is the phone done forever or will a replacement battery allow it too boot properly?

 

[WorzelGummage]

It probably just needs a new battery to be honest. You can pick one up for around ?10 or so. Does the phone boot up O.K. if you leave the charger plugged in?

 

[Alex Johnson3]

No the OS will not boot even when plugged in. Thats normal with drained battery i think though. I will probably pick up a new battery i just wanted to collect some more info first. Makes me nervous given that it wouldn't boot even with a power supply. The third battery contact must be some kind of security feature. hard to find info on though.

 

[Alex Johnson3]

I tested the phone with another focus owners battery. It works. So apparently you cannot improvise a power supply for your phone ... unless you are very clever. The third contact must be important after all. Not sure exactly what it does but the OS will not boot without it.

 

[RTGent]

Not booting when plugged in didn't make sense to me either, but I experimented with my retired cracked-screen-but-still-working Focus; and, without a battery, plugging in does nothing -not automatically, not with the power button, and not even with the 3-button hard reset. I suppose this simulates inserting a truly dead battery. Good luck, and I hope it is just a battery with yours.

I still love the Focus, having just set up my third, with the-same-32gb-card install, a couple of weeks ago.