The customer sent us a faulty iPhone X. His iPhone X once fell into the water, and he picked it up and found that the iPhone was in recovery mode and reported a 4013 error. Do you know how to fix this fault? Please read the following article.

According to the customer's description, the iPhone fell into the water, but did not drop the line. In this case, we can rule out the baseband problem.

After receiving the iPhone X, we first restored the iPhone through iTunes, and iTunes reported an unknown error 4013, which is the same as the iPhone baseband issue.

Exit the recovery mode, remove the iPhone, and connect it to a DC power supply to check the iPhone current. When the iPhone screen is not connected, the iPhone X can enter the IOS system. When the front receiver flexible cable is not connected, the iPhone can be opened smoothly.

Observe the iPhone display screen under the Stereo Zoom Microscope, we found the iPhone receiver has the trace of the water.

Remove the front receiver sensor flex cable, we found the photosensitive lens also has the traces of corrosion. Use QUICK 861DW rework station to separate the light sensor, the solder pad has been corroded.

Handling the corroded solder pad, apply the tin, and use green UV oil to cover the area where the copper is leaking, and then install the light sensor back to the solder pad.

Assemble the iPhone and test it, the iPhone is turned on successfully, and it can enter the IOS system properly, the functions tested are normal, the light sensor is normal, the Face ID is normal.

This failure is caused by a short circuit in the corroded iPhone X front receiver light sensor, which then causes iTunes to be unknown 4013.

If you need any help when you repair your mobile phone,please contact us on www.vipprogrammer.com.