There is an iPhone X whose Face ID is not available and the true tone function is also disabled. We need to find out the point of failure and fix it.

Watch the video:

Step 1: Disassemble the phone and check the ear speaker flex cable

First turn off the phone. Use pry tool to open the screen. Disconnect the screen connection flex cable and ear speaker connection flex cable, and put the phone aside. We can see that the ear speaker flex cable is broken because it's squeezed.

Step 2: Remove the ear speaker flex cable

Now remove the ear speaker flex cable screws and the ear speaker flex cable. Then remove the camera bezel ring and the protective insulation sticker on the joint between the sensor flex cable and the ear speaker.

Step 3: Remove the ear speaker, floodlight sensor and proximity sensor

Use a soldering iron at a temperature of 300 degrees to disassemble the ear speaker and sensor flex cable. Also use a soldering iron at a temperature of 300 degrees, place the sensor flex cable floodlight sensor on the soldering iron to heat it to remove the floodlight sensor. And then disassemble the proximity sensor. 

Step 4: Install the new sensor flex cable

Take out a new ear speaker sensor flex cable (the sensor flex cable that can support the replacement of components). Place a soldering iron at the welding position of the proximity sensor for heating and install the proximity sensor. Place a soldering iron at the welding position of the floodlight sensor for heating and install the floodlight sensor. Weld the sensor flex cable to the ear speaker, and paste back the insulation sticker.

Step 5: Install the phone and test

Refold the sensor flex cable according to the components for easy installation. Take out the screen and put back the camera ring. Install the folded sensor flex cable back on the screen, fold the cable according to the installation position. Next install the screen back to test. We can see now the Face ID function is normal and the true tone function is also normal.