Solution: iPhone 6S Plus iTunes unknown error 4013

When we use iTunes to restore the iPhone 6S Plus, it reports an unknown error 4013. As we know, the iTunes error 4013 is very common, and it could be caused by many reasons. Here are some solutions for fixing this problem.

1. Use another USB port or data cable

The faulty USB port or data cable can cause this iTunes 4013 error, so we need to check USB port and data cable, we can try another USB port and iPhone data cable.

- Find a good quality iPhone data cable

- Plug into another USB port on the computer

- Restore the iPhone with iTunes

We confirmed the cable and port is working, and the connection between is good, but the iPhone still failed to restore and reports iTunes error 4013.

2. Force restart iPhone 6S Plus

There are many simple problems can be fixed by force restarting in software aspect, the operation of force restarting is very simple.

- Please press and hold iPhone home button and iPhone power button at the same time

- Keep pressing the both buttons for 10 seconds

- Release both buttons when you see the Apple Logo appears on the iPhone display screen

However, after force restarting, the problem for this iPhone has not yet been solved.

Next we are going to check iPhone hardware aspect.

3. Disassemble iPhone 6S Plus

Use phone opening tools to disassemble the iPhone 6S Plus, remove the iPhone display screen, disconnect the iPhone battery, and then remove the iPhone motherboard.

We found this iPhone has traces of being repaired; the iPhone baseband IC and iPhone baseband power IC has the traces of soldering.

4. Reballing those chips

Reballing the tin on the chip, and then solder the iPhone baseband IC and iPhone baseband power IC. Now connect it to the computer to test it.

Use iTunes to restore it, when the white Apple logo appears, it stuck on progress bar and won't move, according to our experience, this problem mostly is caused by iPhone Nand flash.

5. Replace the iPhone Nand flash

Use digital multimeter to measure the each power supply on the iPhone Nand flash, all data measured are normal.

Directly remove the iPhone Nand flash, and then install the new iPhone Nand flash. Now connect it to the PC, use iTunes to restore it, now the progress bar goes smoothly, and then it enters the activation interface.

Finally, install the iPhone 6S Plus, get into IOS system to test all functions, they all works well.