With the introduction of the iPhone X in 2017, Apple Inc. introduced the Face ID feature. This feature improved the security of the Apple iPhone by almost 20 times compared to Touch ID while also providing additional convenience for the user. Since then, Apple has released several models of iPhones and iPads that come with the Face ID feature. However, it can be troublesome when Face ID is not working, causing inconvenience.
There are some traditional methods for fixing Face ID issues that involve disassembling the phone, welding, and aligning the device, which is time-consuming and labor-intensive. To solve this problem, REWA Tech introduced the latest and innovative REFOX RP30 multi-functional programmer. The RP30 can not only solve iPhones with Face ID issues, but it can also restore battery health and the true tone function of iPhones. It is our belief that by mastering the use of this device and technique, one will be able to greatly increase the efficiency of iPhone repairs.
REWA Tech understands the complexity of the Face ID repair or solution for iPhones, which is why we have designed a very simple solution for you to use. The only thing you need to do is to follow a few simple steps in order to resolve the issue.
The first thing we need to confirm is whether the failure of Face ID was caused by the dot fusion projector or not. So we turn on the phone to check Face ID. The screen shows that there is a problem detected with the TrueDepth camera. Face ID has been disabled. Then we dial the number to see if the proximity sensor and flood illuminator work properly. While focusing, the camera shows move farther away when set to portrait mode. Therefore, we can make a preliminary judgment that the issue of Face ID failure is caused by the dot fusion projector.
After judgment, place the phone screen face down on top of the heating pad to heat it. We choose to use a screen opener to take the screen off and remove the battery and Face ID.
Next, put the battery and screen back into the phone and connect the phone to the computer. Then link the Face ID to the RP30 Projector for testing. The results show that the dot projector was fused. So we can use the latest solution to repair it.
Back up the data on the dot projector and connect the programmer to the high-voltage power cable.
Click activate and wait for the activation process to be completed. After the activation process, snap the dot projector cable onto the programmer and then write in the data that has been previously backed up. Then remove the dot project cable and snap the Face ID.
Be sure to pay attention to the folding process. If you have doubts about this, you can check our video or contact us for further discussion.
Connect the Face ID to the programmer again for the test. The test result is normal. Put Face ID back on the phone and install the battery and screen. Turn the phone on to test. Face ID can be set normally and unlocked successfully.
Above is the latest Face ID repair solution shared. Since this is a very simple and easy-to-follow solution that requires no soldering, level 2 technicians can now easily correct complex Face ID problems.
Fixing Face ID issues on an iPhone used to be a complicated process that required disassembling the phone and performing complex operations. However, with the introduction of the RP30 multi-functional programmer, level 2 technicians can now easily fix complex Face ID problems without soldering or complicated operations. This not only saves time but also reduces labor costs, making it an excellent choice for cell phone repair shops looking to improve their efficiency and customer satisfaction.
The no-soldering solution for fixing Face ID represents a significant advancement in the field of phone repairs. The step-by-step process for using the RP30 programmer is easy to follow, and the results are impressive.
Looking for a Coupon to save on RP30 programmer? Visit our coupon page or apply the coupon code from Wethrift REWA Page.
With the diffused application of Face ID on iPhone X - 11 series, Face ID failure also appears at a high frequency. As our previous Face ID teardown video has introduced, Face ID can be easily damaged and hardly repaired. If the problem is related to the flex cable, then it’s simple. However, based on statistics of REWA chip-level motherboard repair service , Face ID failure is caused by damage of the Flood illuminator/Dot Projector in most cases, which can not be repaired.
Today, we want to share a case about ‘move iPhone a little lower/higher when setting up Face ID’ and show you how our technicians find out the fault in 3 minutes with the help of REWA exclusive repair tricks on Face ID troubleshooting. Let’s get started!
The phone keeps sending messages: ‘move iPhone a little lower/higher’ during the setting up process of Face ID. It means that Face ID cannot be set up successfully on the phone.
Now, let’s find out the fault step by step.
Step 1 Test The Flood Illuminator
Based on REWA exclusive repair tricks, let's start with the Flood Illuminator. There are two important Face ID parts whose behavior relies on the support of the Flood Illuminator. In our daily repair work, we can test the Proximity Sensor and the Ambient Light Sensor to confirm whether the Flood Illunmunator is working normally.
Let’s make a phone call to confirm whether the Proximity Sensor is working. During the phone call, cover the top of the screen with one hand. We can see that the screen turns black immediately. Judging by this, the Proximity Sensor is working normally.
Next, test the Ambient Light Sensor. Set the screen brightness to the lowest and then hold the phone under a bright light. With the screen getting brighter, we can confirm that the Ambient Light Sensor is also working normally. Judging by this, the Face ID failure is not caused by Flood Illuminator.
Step 2 Test The Front Camera Parts
Let’s move on to the next step of face id not working - test the front camera parts.
Open the camera app and swipe to Portrait Mode. The background is not blurred, which is abnormal.
Step 3 Observing The Dot Projector
At the Portrait Mode, there is no flashing red light from the Dot Projector. But the Dot Projector should emit flashing red light in normal status. We can confirm now that the Dot Projector has malfunctioned. This is the fault that causes the Face ID to set up failure. And the problem cannot be fixed.
The three parts ( infrared camera, flood illuminator and dot projector) are paired to the phone. Damage of any one of them can cause Face ID failure and such an issue is irreparable.
Right now, Face ID failure has become a common problem in our daily repair work. Whether the problem you are dealing with can be repaired or not is really an important thing for repair technicians. Don’t worry! REWA exclusive repair tricks on face id not working can be a great reference for repair technicians to find out faulty positions and improve repair efficiency.For details of this case, please check out the YouTube Video below.
Wanna learn basic knowledge about iPhone motherboard, master iPhone micro-soldering techniques, understand the work-flow of different iPhone circuits, master troubleshooting processes of different iPhone issues, and learn detailed screen/back glass refurbishing steps?
REWA Academy is a platform that provides repair technique learning, practical demonstration, and idea-sharing for practitioners in the electronic repair industry.
Hot Air Guns are commonly used for desoldering/soldering in Face ID repair. However, the operation of a hot air gun is difficult and it can easily bring damage to components. And that’s why REWA LAB brings you this brand-new Heating Platform. Specially designed for Face ID repair, the heating platform can heat Face ID parts evenly and efficiently with simple operation.
1. Supports motherboard Separation & lamination for iPhone X/XS/XS Max/11/11 Pro/11 Pro Max2. Preheats the Truedepth Camera System Module and Earpiece Flex Cable to repair Separate Front Camera & Infrared Camera Separate the glass on the Dot Projector Swap the Flood illuminator, Proximity sensor, and Ambient light sensor to a new flex cable 3. For iPhone 11 series USB Module repair(Featured Product - iFace Dot Projector Detector for Face ID Repair)Best choice repair tools for face ID not working
For more product demonstrations, click on the video below
Some people may come across such problems when using the iPhone with Face ID - iPhone continues to prompt "Move a Little Lower/Higher". But no matter how you move, you can’t reset the Face ID. You can try the following methods to solve the problem:
iPhone X and later model restart method: please press the side button and any volume button until the slider is displayed, then slide the slider to shut down; then press the side button until the Apple logo appears.
If it is a problem with software or temporary system failure, it is generally resolved after reboot.
Please check if there is a stain or occlusion near the front camera, and clean it with a lift.
If the device has touched or fallen into the water before the problem occurs, it may cause the Face ID not working. Please bring your device to Apple after-sales.
Understand if the iPhone is water damaged by the indicator:
Most iPhones are equipped with an LCI that can be seen from the outside. The LCI can tell if the device is not exposed to a liquid or aqueous liquid. Normally, the indicator should be white or silver. But after contacting the water or aqueous liquid, it will become red.
To determine if the LCI of your device touches the liquid, you can refer to the following picture to help you see the LCI. Please use the lamp magnifying glass, adjust the angle of the light or device until you can see LCI.
If the device is not accidentally water damaged, you can try to update the system to the latest version. If the problem is still unable to resolve, you should send your device for repair in no time.
Recently we got many messages about Face ID not available after screen replacement from our clients, which surprised our technicians greatly. Since the screen replacing would not affect face ID function at all according to our practical verification. However, REWA has done some further researches and will share you the detailed analysis and solution for iPhone X face ID failure caused by damage of flex cable after repair here.
How does face ID work?
First, let’s understand how face ID works. The whole functional area is dubbed the “TrueDepth camera system”, which is made up of flood illuminator, infrared camera, front camera, dot projector, proximity sensor, ambient light sensor, speaker and microphone. Speaking of which, have you read iPhone 8/X Ambient Light Sensor Issues ? Every time you glance at your iPhone X, the flood illuminator detects your face with infrared light and forms an image. Then the dot projector will project out over 30,000 invisible infrared dots over your face to create a 3D map. Last, the infrared camera reads this map and sends the data to neural networks to create a mathematical model of your face. Your iPhone X will check that mathematical model against the one that you've set up and stored on your device to see if it's a match, and if it is, it will unlock your phone.
How do we repair?
According to the description, this iPhone X was dropped once. However, the face ID is in normal status. It fails to work until a replacement of screen assembly. With all the knowledge, we begin our repair.
Power on the phone and it shows “unable to activate Face ID on this iPhone” . So we resort to resetting face ID. Go to Settings > Face ID & Passcode > Reset Face ID. We get the message “Face ID is Not Available, try setting up Face ID later” . Our initial judgment is that the unavailable Face ID might be caused by misoperation in the screen replacing process. Therefore, next thing we do is to check flex cables that are related to Face ID.
Disassemble the phone. And check the Infrared camera and dot projector module under Microscope first. Nothing goes wrong. Then move to the Flood illuminator module on the earpiece speaker assembly. Check the connector and flex cables carefully. Still, nothing goes wrong.
Then remove screws. And detach the earpiece speaker and front sensor assembly from the phone. Be careful not to damage flex cables in the process since the Flood illuminator module is bonded to glass lens with double-sided tape. We can see clearly that the flex cable where locates the Flood illuminator module is fractured at the edge.
Since the Flood illuminator module is an essential part for Face ID circuit, damage of the flex cable can result in not working of it, which can absolutely affect normal working of Face ID. Also, as flex cable repair is difficult, we can solder the Flood illuminator module to a new flex cable. To replace with a new flex cable, we need to separate the earpiece speaker and the ambient light sensor module from the earpiece speaker and front sensor assembly first. Heating with Soldering Iron, the ear speaker was separated successfully. Then, secure the flex cable in the place with High-Temperature Protective Tape for further separating the ambient light sensor module flex cable. Soldering Iron and Hot Air Gun are required to remove this flex cable. Once done, remove excess tins on the flex cable with Soldering Iron and clean with PCB Cleaner.
Now the fractured flex cable is separated completely. Next thing we do is to replace with a new flex cable. Remove the Flood illuminator module on the flex cable first. Prepare a new flex cable. Apply some Paste Flux to the bonding pad. Align the Flood illuminator module in place with the new flex cable. Be careful with the direction. Then solder with Hot Air Gun. Remove residual glue on the module afterward.
The repair part is almost over right the moment. Next thing we need to do is to re-solder the ambient light sensor module and earpiece speaker. However, the soldering of the ambient light sensor is the most difficult part of this repair. Whatever, let’s do it. Apply some Paste Flux to the bonding pad of ambient light sensor module. Then apply tins to the bonding pad with Soldering Iron . Clean with PCB Cleaner. Apply some Paste Flux to the bonding pad again. Get the detached ambient light sensor module flex cable in position. Secure the flex cable with one specific position soldered by Soldering Iron with curved nozzle first. Then use Soldering Iron with cutter nozzle to complete the remaining soldering process. Clean with PCB Cleaner afterwards. Now we need to solder the earpiece speaker back to flex cable.
It’s time to get the earpiece speaker and front sensor assembly assembled to the display assembly. Re-assemble the phone and test. Press power button to power on. Go to Settings > Face ID & Passcode > Set up Face ID . Face ID can be set up successfully. Press the power button to lock the screen. Press the power button again. The screen lights up. Glance at the iPhone X. The screen can be unlocked automatically. Fault cleared.
questions about iPhone X Face ID Not Working After Repairing Tutorial, welcome to comment below or ask a question on ASK Forums .
Click below if you are interested in the Tools & Spare Parts used in the video. For more details and latest price please feel free to contact email@example.com
* Integrated Mobile Phone Repair Platform
* Tri-wing Screwdriver - Type 2
* Straight Tweezer - Type 3
* 4x Optical Microscope - KS7045
* PCB Cleaner - 250ml
* BGA Strip Flux Soldering Paste
* Anti-static Plastic Pry Bar
* Heat-resisting Adhesive Tape - 5.0mm
* 100g Solder Wire - Type 1
* iPhone X Replacement Parts
Visit REWA online shop for more parts and tools.
I wanna learn basic knowledge about iPhone motherboard, master iPhone micro-soldering techniques, understand the work-flow of different iPhone circuits, master troubleshooting processes of different iPhone issues, and learn detailed screen/back glass refurbishing steps——You can visit REWA Academy.
iPhone X is the first model with the Face ID function. In the traditional model, the authentication method called "Touch ID" is adopted, but the "Face ID" is unlocked by turning your face steering screen. Here, we will show how to set it and how to solve some face id not working problems.
I want to set up Face ID and unlock it, but I don't know how to set it! This article will tell you how to set the Face ID for this kind of iPhone user.
 Select "Settings" → "Face ID and Password".
Click "Set the Face ID".
 Hold the device vertically, then place the "face" in front of your phone, then tap "Start".
 Make sure your face is on the center of the frame, and then moves slowly with circumferential motion. If you can't move your head, click "Assist Features Options".
 After the first scan, click "Continue" and repeat the same operation.
 Click "Complete" to complete the settings.
First, make sure your TrueDepth camera and face are not covered by anything. Also make sure your device is portrait, and your face is facing the screen. If you still can’t set up, check the update and restart.
Since the operation is the same as the above iPhone X / XS, the figure is omitted.
 Open in the order of "Settings" → "Face ID and Password".
 Click "Set the Facial ID (Settings)".
 Hold the equipment vertically, so that your face is in front of the phone, then click "Start".
 Move the face to the center of the picture, and then move slowly with circumference. If you can't move your head, click "Assist Features Options".
 After the first scan is completed, click "Continue" and then perform the same operation again.
 Click "Complete" to complete the settings.
What should I do if I can't register facial information? And can you register your face ID even if you wear glasses? People wearing glasses are particularly worried.
I can't use a human face ID to register your face information! Is this in the camera?
If there is not fully registered facial information, it may be a TRUEDEPTH camera failure. If a fault occurs, you need to repair it, so bring it to the Apple Store or transport store.
[Reference] Apple Support Official Website:
If you don't wear glasses, you can use the Face ID when you certify. If you do not get authentication in the state of the glasses, you will be registered with the state of the glasses and the state of glasses. Set - Open "Face ID and Path Code", enter the path code, click " Set another look. " Afterward, please follow the steps.
An error message appears on the FACE ID?
Although the facial information has been registered on the face ID, an error message can be displayed without recognition. Let's take a look at this time.
When setting the FACE ID, a message "Moves the iPhone slightly"
When this message is displayed, let's change the lighting environment. If it is too bright or too dark, it may not be able to successfully identify. In addition, protect paper is not recognized and cannot be identified, so let's try to make a protective film at a time. If there is no improvement, please restart.
"Attack measures" When "currently cannot use"
First, let's check and restart the update. If it is also unreliable, reset the facial ID and register the facial information again. If this is not improved, it may fail, so please contact Apple support or bring it to the Apple Store.
"When this iPhone can't activate the Face ID"
This problem seems to have occurred after the application is updated. If you cannot use it after restarting the device, you may need to fix or replace it.
Today, REWA LAB will walk you through a detailed explanation of three dot projector repair solutions and show you the three most popular dot projector repair tools in the industry. Which one is the best choice for repair shops? You will get the answer you want from this blog.
The fault is face ID not working - move iPhone a little lower/higher. Here we will introduce three different repair tools to fix the problem, which include JC, LUBAN, and I2C.
Firstly, we need to connect the dot projector flex cable with the three repair programmers directly. Then we will know immediately whether the dot projector flex cable is normal or not.
Notes: the JCID programmer requires official authorization.
The repair solution of JC and I2C is to burn data of the original dot projector flex cable onto a new dot projector flex cable.
While the repair solution of LUBAN is complicated.First of all, we need to put the phone into recovery mode. The following step is to connect the repair programmer to computer. Then we need to pearl unbind the encryption chip on the original dot projector module from the phone with the help of the software. The next step is to replace the original encryption chip and the capacitor on the module. And then pearl blind the new encryption chip to the phone.
Dot Projector Flex Cable
A grinding tool is needed in this step for the three repair solutions. So firstly, we need to grind the bottom bracket of the dot projector flex cable. Then we should separate the crystal from the flex cable carefully with a pry knife. The following step is to take out the dot projector flex cable carefully and continue to take down the MOSFET with the pry knife. After that, we also need to connect Pin 2 and Pin 3 of the MOSFET by jumping a wire.
Dot Projector Repair
With JC and I2C, all we need to do is to solder the dot projector module onto a new dot projector flex cable. While for LUBAN, this can be really difficult. In addition to the whole MOSFET thing, we also need to replace the encryption chip and the capacitor on the dot projector module. And before replacing the encryption chip with a new one, we have to solder a connecting FPC. What’s more, if the connecting FPC hasn’t been soldered well, you might get stuck in pseudo soldering or bridging. Once the encryption chip and the capacitor have been soldered properly, we need to put the phone into recovery mode. After that, we can connect the repair programmer to computer. Then we also should pearl bind the encryption chip to the phone with the help of the software.
We can test by connecting the dot projector flex cable with the repair programmer. Once we have confirmed that the dot projector flex cable has been fixed. The following step is to glue the crystal to the dot project flex cable carefully. After that, we can assemble the phone and test. We can see face ID setup can be completed successfully.
Visit our online shop for more parts and tools.You can also visit REWA YouTube Channel to check our video.
Face ID Not Working 'Move iPhone a Little Lower/Higher' is usually caused by damage to the dot projector and the problem is confirmed to be almost unrepairable. However, there is finally a solution to fix the problem. Today REWA LAB will show you the latest dot projector repair technique!
When trying to set up Face ID on the iPhone, we get the message 'move iPhone a little lower/higher'. Next, switch to the front camera, we found that the name of the lighting effect ‘Natural Light’ stays the same when the camera detects a person's face. What's more, the pop-up notification keeps saying ‘Move farther away’. Normally, when Portrait mode is ready, the name of the lighting effect ‘Natural Light’ should turn yellow. Judging by this, the dot projector or relevant circuits of the dot projector might have malfunctioned.
Take apart the phone and remove the display assembly first. We can see that the dot projector has been water damaged and the crystal on the dot projector is broken. Take out the front camera assembly carefully. Here we recommend using a repair programmer to check the dot projector flex cable. Connecting the dot projector flex cable with the programmer, the results show ‘Fusing’ which means the dot projector flex cable has been damaged. We need to burn data of the original dot projector flex cable onto a new one and then replace the broken crystal.
In the first step, we should separate the crystal from the cable. Compared to traditional operations with a hot air gun, we prefer to use an intelligent preheating platform. Put the dot projector into the matching rubber mold and separate the crystal from the flex cable carefully with the blade. Next, we use the repair programmer again to burn the origin data onto the new dot projector flex cable. After completing these two steps, we need to solder the dot projector module and glue a known-good crystal. For detailed instructions, click on the video at the bottom of the article.
Reassemble and Test
Apply double-sided adhesive tape on the backside of the front camera, and adhere the dot projector flex cable to the right position. Get the front camera assembly installed and get the logic board assembled and buckle the display assembly. Face ID can be set up successfully, and the phone can be unlocked with Face ID this time. Tips: The double-sided adhesive tape used here is for the test. We need to glue the dot projector module onto the flex cable after fault clearance.
Soldering Station & Material Set
Medium-Temperature Solder Paste
Hot Air Gun
Intelligent Preheating Platform
Visit our online shop for more parts and tools.You can also visit REWA YouTube Channel to check our video.
As a facial-recognition technology initially launched on iPhone X, Face ID has been applied to latest iPhones, including iPhone XS，XS Max and XR. With this amazing Face ID system, users can unlock their devices by scanning and confirming facial identity. Whether you are wearing a hat, putting on glasses or you are in the dark.
There are 8 components packed into the front of the phone.
Ambient Light Sensor
Dot ProjectorThe infrared camera, the dot projector and the front camera are located on the back glass assembly. The flood illuminator, the proximity sensor, the ambient light sensor, the speaker and the microphone are located on the display assembly. Please be careful when disassembling or repairing the phone. Damage of any component will cause Face ID failure.
Next, we will disassemble the flood illuminator module and the dot projector and find out the reason why Face ID can be so easily damaged.
Let’s disassemble the flood illuminator module first. Pry open the glass cover with a blade. We can see that there are many holes on the flood illuminator that are arranged in a matrix of 11x11. The chip is connected to the circuit board with the help of gold wires. Once water damaged, these holes can be blocked. And you will be faced up with Face ID failure.
Chip 1 is an unencrypted chip. Since some repair technicians have replaced it before, our guess is that chip 1 might be a boost chip or an EEPROM chip. So chip 2, chip 3, or chip 4 might be the encrypted chip. Still, due to the difficulty of replacing, no one has verified that. As you can see, with thousands of components integrated, the composition of the flood illuminator module is very precise.
Chip 2 is the flood illuminator.
Chip 3 and Chip 4 are proximity sensors that are responsible for receiving and transmitting respectively. The infrared light emitted from the two proximity sensors could be a single dot or a single set of dots. Independent of each other, the three chips are indispensable. And this is what you should know about the flood illuminator module. Let’s move on to the dot projector.
The camera parts of iPhone X work in the same way as front cameras of other iPhone series. Now we will focus on the dot projector. The outer layer of the dot projector is sealed with resin and protected by metal welding techniques. Pay attention to these welding points.
They can easily fall off once the phone is dropped. And once off, they cannot be restored. When disassembling, we need to cut open the outer metal cover at first. Then heat with the Hot Air Gun and remove the resin with tweezers. Once the dot projector has been detached, we can see a crystal that looks just like a diamond lens. The infrared light is emitted from here. Then reflected by the crystal. Its projection range is determined by the lens afterwards.
Pry open the crystal, here we can see the complete internal structure of the dot projector.
The chip on the left is used to store data, whereas the chip on the right side acts just like a projector. We can see that there are thousands of dots arranged here. The infrared light is emitted from here. Since necessary power supply is needed for chip on the right side to work normally, once water damaged, circuits here are most likely to get short. Which can also result in Face ID not working. And please be noted that the chip is exposed without black adhesive seal. So it can be easily damaged once water-damaged or dropped. What’s more, it also can not be restored once damaged. And this is the internal structure of the dot projector. Let’s continue with the crystal part of the dot projector.
We can see that there is a concave lens and a convex lens on the crystal. And the two are made of glass. Once dropped, Face ID can also be affected.
Judging by what we have learned during the disassembling, main circuits of the Face ID are exposed. Once water damaged or exposed to a relatively humid environment, there might be electricity leakage or short-circuit problem that can result in Face ID failure. What’s more, most of the Face ID parts are made of glass. Once dropped, Face ID is most likely to be unavailable.
In summary, Face ID can be easily damaged and hard to be restored. Therefore, please be very careful in daily use. Make sure the phone is protected from water-damage or heavy falling. Repair technicians must exercise caution when repairing the logic board or replacing the display assembly. Also, for those in need, we have summarized repair experience of REWA repair technicians and hereby present you the following troubleshooting guide on common Face ID failure.
Here is the detailed video for your reference.
When repairing iPhone logic boards, we identify the issue first, find out why it occurred next, and figure out how to fix it in the end. This is a general process adopted by professional repair technicians around the world.
Wanna be a professional repair technician and handle iPhone tough repair? You need systematic training courses on REWA Academy.
Just click the cell phone repair course link below to know more!
iPhone X Series Logic Board Repair Course
iPhone Logic Board Repair Foundation Course
iPhone Logic Board Repair Handwork Course
iPhone Logic Board Repair Work Flow & Troubleshooting Course
iPhone Logic Board Repair Cases Course
Cell Phone Broken Screen Refurbishment Course
iPhone Motherboard Repair Course Complete Package
What you have to say about Face ID? Please leave your comment below.Related Cell Phone Repair Guides:
iPhone X Face ID not working repair guide
iPhone 7/7p home button not working
Fix iPhone no service
Fix iPhone X keeps restarting
Ahead of the launch of the iPhone 12, rumors claimed that the new model will both feature Touch ID and Face ID. Now that these myths have been dispelled, the iPhone 12 retained the Face ID function that proves to be a more secure and effective recognition technology.
Though Face ID is handy, numerous users found that Face ID is not working sometimes, in which they have no choice but to enter the passcode to unlock.
There are generally several reasons why Face ID is not available.
Like passcode unlock, Face ID also has a security protection system. Once the system is activated, you must enter the passcode to complete the extra security verification.
1. The device just turns on or restarts.
2. The device is locked for more than 48 hours.
3. In the past six and half days, the device hasn’t been unlocked by a passcode and the device hasn’t been unlocked by Face ID in the past 4 hours.
4. The iPhone receives remote lock instruction.
5. Face ID unlocking has failed 5 times.
6. Simultaneously press and hold the side button and either volume button until the “Slide to power off” and “Emergency SOS” sliders appear on the display.
The Face ID may also fail in some conditions:
1. Face Covered
If you wear sunglasses or a hat, it will prevent your Face ID from working successfully.
2. Camera Covered
If you apply a protective film on your phone, or there is dirt near the TrueDepth camera, the sensitivity of Face ID may be affected to some extent.
3. Hardware Problem
If you see "A problem was detected with the TrueDepth camera. Face ID has been disabled", it means that iOS has detected hardware damage of the device and it needs to be repaired.
Although Face ID is convenient, the repair cost of hardware damage is also very high. If there is a problem with Face ID, you can first try to solve it by resetting and restoring the system. If it is determined to be a hardware problem, you’ll probably have to take your iPhone to your nearest Apple Store for repair.
Feel free to leave any other questions you have about Face ID down below in the comment section.