The most common iPhone Touch ID failures mainly include Touch ID failure or Touch ID not working properly.
Before starting any repair steps, check your iPhone's home button to make sure the iPhone home button is free of water, oil, any other liquid, dirt and dust.
If there is dust, you can clean it with a Non-dust Cleaning Soft Cloth. Be sure to avoid using liquid cleaner directly on the home button. Of course, when using touch ID, make sure your fingers are free of water, oil, any other liquids, dirt and dust.
Calibrating the fingerprint
When calibrating, hold the iPhone in the usual way. Then, calibrate your finger. Be sure to place your fingers wherever possible, including the edges and tips of your fingers; all parts of your fingers should be scanned. Also, make sure your finger touches the metal ring around the home button. If you are using a case or screen protector, make sure it does not overwrite the home button or the surrounding ring. If yes, remove the case or screen protector and try again.
If you have a new version of iOS, you should download and install it. This is usually necessary because each new version can resolve various errors that may exist on your device and can resolve touch ID issues. You can update iOS wirelessly, but before you start, back up your iPhone to iCloud.
If your Touch ID doesn't work because of hardware damage, it can be very difficult to repair. Because the Touch ID chip and the motherboard absolutely match each other. If you only change the new home button, the Touch ID feature will disappear as the only chip will change. So if the home button is unfortunately broken, how do we fix it without losing the Touch ID? We have successfully fixed an iPhone 6 Touch ID that doesn't work. Proceed as follows.
2. Scrape off the coating from the wire on the back. Apply some BGA paste flux, then solder the tins with soldering station
3. Cut the wires and align them properly, heat and solder with a heat gun. Turn the flexible cable to the reverse side and solder with wires. Then use a Digital Multimeter to test for short circuits
5. Finally, we installed the LCD components and tested them, and the fingerprints worked well.
Hope the way we share is helpful to you. For more professional iPhone repair skills and equipment, please visit www.vipfixphone.com. If you have other iPhone-related questions, please leave a message in the comments.