iOS 13 update has again brought the True Tone missing problem to some iPhone users. Well, REWA LAB has worked out a new solution to fix the problem. We will take iPhone XS as an example and show you how to restore True Tone of aftermarket screens step by step . I'm not so sure about a workaround for the display; if I recall correctly you may have to unsolder a chip from the old display and solder it onto the replacement. In a blog post, iCorrect explains why Face ID is disabled on the iPhone 13 when replacing the screen and also gives context ever since Apple introduce this technology with the iPhone X:

I vacillated between the V1SE and the iCopy device, but ultimately settled on the iCopy. However, it turns out the iCopy software doesn't let you read the screen data from the phone itself, so I had to find another way to get that data without the original screen. This “True Tone” function has improved people convenience to using their phone friendly especially at night time. This function allows the smartphones to adjust screen display white light with change of external environment, automatically. So iPhone display does change with hot or cold environment, in latest iPhone models. These models are: The iPhone 13’s screen IC now not only acts as a ADC, enables True Tone, carries a ROM for the non-genuine message but also now communicates with Face ID. We believe this communication with Face ID is a bug in iOS15. But it shows us a glimpse of how much more complex the screen IC is going to be in the future. We expect the next generations of iPhone to contain 2 biometrics in Face ID & in screen Touch ID. We expect when replacing a screen in future will disable the in screen Touch ID.“According to what I've read online, it would be hard to justify the effort needed just to restore TrueTone on recent iOS versions. Disconnect the battery and remove the original screen. Continue to remove the front panel sensor assembly flex cable. And install the detached cable to the new aftermarket screen. Get the aftermarket screen installed and press the power button to turn on the phone. When we covered the original Phone Repair Guru video, he said that even when you replace your iPhone 13 screen for another original display, a message saying “Unable to verify this iPhone has a genuine Apple display” appeared. You may ask what True Tone is and why is it essential? The True Tone function on the iPhone 8 and upwards allows the screen to have better colour to match that of the original screen, without the True Tone function, the colours will not be as good as what you’d expect with an original screen. How can I use the JC-V1 to enable truetone after I have lost the function from a previous screen repair? Last week, 9to5Mac reported that Face ID stops working if you replace the iPhone 13 screen with a third-party repair. Now, a new video shows that it’s possible to replace the screen and make facial recognition work, but it’s not simple.

Lost or degraded functionof the ambient light sensor, causing the screen to dim or brighten incorrectly For most customers, visiting a professional repair provider with certified technicians who use genuine Apple parts is the safest and most reliable way to get a repair. Theseproviders include Apple and Apple Authorized Service Providers, and Independent Repair Providers,who have access to genuine Apple parts.*Repairs performed by untrained individuals using nongenuine parts might affect the safety of the device or functionality of the display. Apple displays are designed to fit precisely within the device. Additionally, repairs that don't properly replace screws or cowlings might leave behind loose parts that could damage the battery, cause overheating, or result in injury. When repairing iPhonelogic boards, we identify the issuefirst, find out why it occurrednext, and figure out how to fix itin the end. This is a general process adopted by professional repair technicians around the world.Please see video below of the JC V1 data transfer. After you have followed this guide, install the new screen to your device.

We’ve tested it, and it’s true: iOS 15.2 stops Face ID from malfunctioning after you replace the screen on an iPhone 13, outside their official repair channels. Royal Mail and the courier company, DPD, both offer home collection services, where they will collect a parcel from your house and deliver it to us. You don't need to even visit the post office to arrange it. If you are using these services, please make sure that the insurance covers the value of your device. From our research, the iPhone communicates with the screen through a microchip embedded on the screen.This screen microchip is an integrated circuit (an assembly of electronic components fabricated into a single unit) responsible for translating your analog touch (your finger pressing on your screen creating an analog signal) to a digital signal (for your iPhone to understand as your iPhone is a mini-computer and doesn’t understand analog signals)People are using smartphones more than ever. iPhone users needed a function that can give them relieve in terms of reducing eye strains. We use iPhone in night time or closed room or open space, white light does play important role to increase discomfort level with “True Tone” new function, Apple introduced in 2017. Technically there is a way to get rid of that warning, which is to move the touch module IC from the original display to the replacement. It's a very difficult and delicate operation and probably isn't worth it, to be honest. Outside of that, paying Apple to replace the screen is the only other way to get rid of that warning; screen replacement on the 12 models is available on the self repair program, but you still have to buy the screen from Apple for full price and rent their equipment to do the job. You are now set up, and your V1 is up to date and now compatible with iPhone 11 models. You can now start transferring True Tone and other data onto models from iPhone 8 through to 11 Pro Max