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Solution: iPhone 6s Won't Turn on

The iPhone 6s problem is unable to turn on. Disassembling it by JM-9102 opening Tools, remove the iPhone motherboard and then measure it with Fluke 15B+ Digital Multimeter. When you press the power button there is a large current of 500mA, it is leakage and then won't turn on.

After seeing the ammeter, the first thing we think about is not the iPhone battery voltage leakage, nor the power supply of VCC. After pressing the power button to appear large current is caused by the power supply load in the leakage or short circuit.
First we use a Temperature-sensing method to feel the iPhone where the temperature is higher. After checking, we preliminary judgment the temperature is obviously high near the fingerprint line. Now we're going to check exactly which part is wrong.


Through the soldered Rosin method, we found that the 3D touch tube was obviously hot. This time we have an idea that this is not necessarily a problem with the power supply tube. When we first started repairing the 6 generation VCCMAIN short circuit issue, we found that the electronic switch hot obvious, at first we thought it was broken, but it is not. Anyway, remove the 3D-TOUCH power supply pipe first. After that, provide power to it to test, the iPhone 6S now can be turned on.


The problem was found, but a 3D-TOUCH was not powered. At this point, we're looking for a voltage close to 2.75V near it. The closest to it and nearest 2.75V is the fingerprint 3.0V voltage. When we connect to the 3.0V voltage, the iPhone again shows a large current of 500mA. Now we have an idea, it's not the power supply pipe problem, but the load short circuit. Now, we need to use QUICK 861DW Hot Air Rework Station to solder rosin again.


Finally, we found the culprit, which is a small capacitor. After remove the small capacitor by Precision Titanium Alloy Tweezers, now the iPhone can be turned on smoothly, and the 3D-TOUCH is back to normal.


Summary: This phone repair case tells us the repair man a truth, the reason why the power supply IC or power supply tube is hot is not necessarily that it's broken; mostly it is caused by the leakage or short circuit of the rear load. We can understand it like this, our home switch is hot, and usually it is caused by our home appliances burned out after the leak.

More cell phone repair tutorial read at www.vipfixphone.com
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