Unknown Error 14: iPhone 6S Plus failed to restore(Troubleshooting Tips)

The iPhone 6S Plus failed to restore, it reports unknown error 14. What's going on? When we use iTunes to flash it, the SN cannot be recognized, and it will reports iTunes error 14. Here to to get troubleshooting tips to fix it.

According to the our experience, we suspect that it's the problem with iPhone Nand flash.

Disassemble the iPhone, take out the iPhone motherboard, and then carefully remove the iPhone Nand flash. Check iPhone bitmap on WUXINJI Dongle, and then measure the diode data with multimeter, we found that the resistance value of iPhone Nand flash solder pad M6 Pin is infinitely large.

This pin passes through the R1501 resistor and pulls down, there is no resistance value when measured it with Fluke 15B+ Digital Multimeter, now we're judging that the R1501 resistor is damaged.

Directly replace the R1501 resistor, and then measure the resistance value of iPhone Nand flash solder pad M6 Pin again, the data is normal. We can check it under the Stereo Zoom Microscope HDMI Camera.

At last, assemble the iPhone and flash it again, now it's done well. After get into IOS, all functions on iPhone tested are works good. The repairs end!