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Fixed: iPhone 6 Won't Turn On


iPhone 6 is directly connected to the DC power supply after short circuit, large current short circuit and iPhone motherboard overheating. We think this is a small problem. When we remove the iPhone, we find that the iPhone charging tube is hot. Remove the shield and apply some rosin. Obviously, the iPhone baseband power supply is damaged. Delete the iPhone baseband power, then connect the iPhone logic to the DC power, the iPhone start, but not display, more clearly check, several pins on the socket are damaged.
 


Remove the socket and clean the pads, re solder the socket. After replacement, iPhone can be turned on normally, but there is no baseband.

Install the new iPhone baseband power supply, but there is no SIM card failure, continue to measure it, and no front and rear cameras. IPhone 6 no front and rear cameras are usually caused by a 2.85 volt power supply. A regulated converter is found directly. Scrape off the glue and weld the jumper. We can check the bitmap in WUXINJI Dongle.

Based the picture, soldering a jumper wire from photosensitive 3V to camera 2.85V, and then test the iPhone camera, the rear camera is normal, but the front camera not. The data measured by Fluke 15B+ Digital Multimeter all is normal. We think the iPhone has been flashed when the camera is damaged. Because there is an ID, so we can't flash the iPhone, and the customer doesn't care this failure, so directly install the iPhone.

After install the iPhone, turn on iPhone, after Apple logo appears 2 seconds, it's automatically turned off. Connect iPhone to the DC power supply, the current jumps from 80 to 160, after a while, it turns 0. According to our experience, we think it's iPhone Nand flash problem.


From the above picture, we can see that this shield cover has been dented by a lot of external damage，it seems the iPhone Nand flash virtual weld. Directly remove the iPhone Nand flash, re-weld it and then install it, but the problem still there.


Now, we need to flash the iPhone, get the ID from customer to flash the iPhone by iTunes. After flashing the iPhone, the problem was solved, it's a system problem.
Learn more cell phone repair tutorials on www.vipfixphone.com

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