Due to the vulnerability of the Face ID parts, it can be easily damaged when the phone is dropped or during screen replacement. And that’s what our blog is about today. iPhone X Face ID Not Available caused by broken flex cable of the Face ID parts. This is also a reminder. Please be careful in your daily use of the phone!
How Does Face ID Work
With user’s face closing to the screen, the proximity sensor starts the recognition process. The flood illuminater helps the TrueDepth camera system determine how much illumination will be needed for face recognition.
The dot projector projects over 30,000 dots in a known pattern onto the user’s face. Those dots are then photographed by infrared camera for analysis.
A 3D map of user’s face are then completed. The 3D model is then compared against the stored template. The phone authenticates the identity and unlocks or authorizes a payment.
Step 1 Test
Press the power button to turn on the phone. The iPhone X shows an alert that says it is ‘unable to activate Face ID on this iPhone’.
Go to Settings > Face ID & Passcode > Reset Face ID. When trying to set up Face ID on the iPhone X, we get the message 'Face ID is Not Available, try setting up Face ID later'.Judging by this, Face ID relevant circuit has probably malfunctioned. We need to check components on Face ID relevant circuit.
Step 2 Diagnose
Take apart the phone and disconnect the battery. We can see that the infrared camera module flex cable is broken. So the fault is probably caused by malfunction of the infrared camera.
Remove the Face ID parts. We can see clearly that the infrared camera module flex cable is broken.
Step 3 Troubleshoot
Fix the infrared camera module flex cable with High-temperature Tape. Then scrap off insulating varnish on the cable with the Sculpture Knife.
Notes: control the force applied when scrapping. The flex cable might be further damaged during the operation.As we all know, the Face ID parts cannot be replaced. So we need to treat the broken flex cable with jumper wiring.
Step 4 Jump-wiring
Continue to apply Paste Flux to the broken flex cable. Then heat with the Soldering Iron and tin the broken flex cable with solder paste. Once done, clean with PCB Cleaner.
Again, apply Paste Flux to the broken flex cable. Here we need the Enameled Copper Wire of 0.02mm in diameter. Heat up with the Soldering Iron and solder the two ends of the wire to the two pins of the broken cable.
Once done, cut off the excess wire with Sculpture Knife.Notes: keep the soldering iron tip away from pins of undamaged cables to prevent these pins from getting shorted.Once completed, check again to make sure that there is no shorted pin or pseudo soldering condition. Clean thoroughly with PCB Cleaner afterwards.
Step 6 Solidify
Once done, apply some UV Curable Solder Mask to the jumper wiring area for insulation protection.
Continue to solidify the flex cable under the UV Dryer Lamp. Stick High-temperature Tape/Solder Joint Sticker on the jumper wiring area to reinforce.
Step 7 Test
Next, let’s assemble the phone and test. Get the Face ID parts and the display assembly installed and the battery connected. Press the power button to turn on the phone. The phone turns on normally.
Go to Settings > Face ID & Passcode > Reset Face ID. Face ID can be set up successfully. The screen can be unlocked automatically.
Tools & Parts Needed
Hot Air Gun Rework Station
Integrated Mobile Phone Repair Platform
iPhone Disassembling Tool Kits
Electron Microscope
You can also visit REWA YouTube Channel to check our video and learn how to fix iPhone X Face ID not available efficiently.