[Galaxy S III Mini Q&A, Help & Troubleshooting] Kirbs82:
Regarding:

Samsung Galaxy S3 Mini GT-I8190 - SIM unlocked version

Hello eveyone.

I'm having one of the strangest problems I've encountered with a phone before and I just can't seem to track down the problem. Please read this thread with an open mind as from what I can tell this is a unique issue that sounds like normal issues.

The main problem is that the phone keeps rebooting. From the get go this sounds like a normal issue with either the battery or power switch but here is the weird part...

It only happens when the phone is fully charged!

IBackground

I have had the phone since release and I have only ever used the stock rom that came with the phone. I don't really use phones much n general except for using it for calls texts and BBC news. I didn't even have a SD Card in it until after the problem started. Everything was running great, I never had any battery problems at all, and then a couple of weeks ago my phone contract expired with Orange and I decided that I would get a SIM only plan with EE.

While waiting for the SIM card to arrive in the post I charged my phone up one day and noticed that I had to power on the device. The phone seemed to power on fine, I could use all features of the phone, but when I turned the screen off for more then 5 or 6 seconds the phone would restart. There would give no indication that it had turned off or that it had powered off in anyway. It would simply just be blank, I'd press the power switch, and it would vibrate once and begin its start up procedure as if it had been turned off completely.

Here is where it gets weird, the phone will keep cycling on its own like this until the battery drains itself through constant reboots until about 85% juice, at which point it begins to operate functionally.

I heard that some people say they had problems with the power switch. I figured that if it was the power switch it then the problem would be consistant and would continue giving me problems when the battery was below 85%. I think I can rule out the power switch as faulty. Naturally I came to the conclusion it must be software, perhaps an APP installed which was incompatible. I tried all sorts of things, regardless I came to the conclusion it needed to be factory reset. Factory reset didn't do anything, still does it. My next thought was Firmware, it must be the firmware that was corrupt. I went through tutorials and rooted my phone, installed recovery software and ended up installing Cyanogenmod 11 (Which looks really beautiful btw, wish I had done that sooner) and buying an SD Card too do so. Still the problem persists! I read that some people had problems with swelling batteries, I replaced the battery completely just incase. £10 wasted, still does it.

At this point I'm starting to get confused. I started thinking perhaps it was the cable providing too much charge to the device, over charging somehow. Tried a different cable and a different power source. Still the poblem persists. I made sure there was no dirt in any of the connectors incase that was causing something. No joy.

So to summerize:

1. Factory Reset

2. Replaced Battery

3. Changed power leads

4. Cleaned device

5. Flashed to completely new firmware

I've completely run out of ideas on what it could be. Why would the phone operate absolutely fine under 85% power? Its just weird! I'd appreciate any help some one could provide me. I've not seen any one else with this problem on the internet. Please let me know what you guys think.

Thanks

Craig.