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Released on September 19, 2014, this 5.5" screen iPhone is the larger version of the iPhone 6.

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Phone restarts at random.

Phone started restarting at random. Battery shows 1% then after plugging it in it will jump to around 48% unplug it and it drops down to 1%. I replaced the battery, yet still have the same problem restarting and battery not showing correct percent. I replaced the charging port and still have same issue. Phone now will only restart when I try to use it. If it is sitting and not being used then it will not restart. I have done a factory reset on it also. Any ideas what else could be wrong?

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Hmmm...I will say that those are symptoms of a bad battery. It is possible that your replacement battery is also defective. Have you tried measuring the voltage directly at the battery connector with a multimeter - if so, what voltage are you reading? Ideally, you would want to confirm that your replacement battery works in another phone or install a known-good battery in the phone that is being repaired.

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Volt check at 3.59 V So I don't think its the battery.


Well, it's not quite that simple :>). Voltage is one thing, ability to drive current is another. The voltage can look fine but what happens to the voltage when you have a high current demand? I did some tests recently on iPad batteries using a electronic dummy load. When the current demand is high, the battery voltage drops down a lot, well below what is needed to boot a device. A weak or defective battery would have the same symptoms yet still show 4.2V when fully charged. It's just that it can't maintain any current drive without dropping the voltage.

So yes, your battery may be fine but don't use just voltage to determine the health. Ideally, you need to eliminate a variable. Use a known-good battery or install the current one in a known-good housing. That's when you can rule it it completely.


Is there any way to test this?


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I'd probably say that it's a bad connector. Plug everything in, let it turn on and then tap it against a surface in a couple different angles. If it turns off when you hit the phone against a surface then it's just a bad connection somewhere on the battery or phone

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