Troubleshoot: iPhone 7 Plus no charge and no voice

My iPhone 7 Plus no charge no voice and no camera function, it makes me feel depressed. How to troubleshoot these problems? Get help here!

First check iPhone Lightning cable, charge port and charger, no obvious damage. Now, connect iPhone 7P to power with charge cable, the iPhone has no response. In this time, we remember that the some iPhone won't charge when using charger, but it will charge when connect to computer, so we try to connect to PC, but still no response. So, now we need to check iPhone 7 Plus hardware.

Disassemble iPhone, remove the iPhone motherboard. First measure the diode data of iPhone solder joints on solder pad with Fluke 15B+ Digital Multimeter, finding that the diode data of iPhone USB IC C3 pin is infinitely large. After check iPhone 7 plus schematic diagram, this signal point is connected to iPhone main audio IC by through resistor R3104.

Remove the iPhone main audio IC and check it under the 7-45X Trinocular Stereo Zoom Microscope, there's a pins dropped and disconnect. Fix the jump wire of the pin, and replace the iPhone big audio IC. Now measure the diode data of USB IC C3 pin again, the data is 480, and it’s normal data. Tested iPhone charge function and iPhone voice function are normal.

Now, for iPhone no camera issue, the details is that iPhone rear camera can't take photos. Carefully observe the iPhone, we found the iPhone rear camera badly deformed, directly replace the new rear camera, the iPhone won't take photos issues has been solved.

Tips:

Usually, there are three reasons can cause iPhone USB control IC C3 pin is infinitely large.

1. the resistor R3104 is damaged;

2. the iPhone motherboard dropped pins and disconnection;

3. the iPhone big audio IC is damaged.