How to Fix Face ID on an iPhone 12 Mini: The Complete Step-by-Step Guide

Face ID is one of the standout features of the iPhone 12 Mini, but when it stops working, it can feel like your phone has lost part of its magic. Fortunately, Face ID issues are repairable if you follow the right steps. In this guide, I’ll take you through the entire process in detail, so even if you’re not an experienced technician, you can understand the method.

 

Let’s dive into the step-by-step breakdown!

 

 

Tools You’ll Need

Before you begin, make sure you have the following tools and supplies:

  • Hot air rework station (set to 175°C, airflow 50)
  • Blade for precision cutting
  • Drill or small cutter to remove brackets
  • JC programmer (like JCID V1SE) for data transfer
  • Soldering tools (thin soldering wire, wick, flux, and iron)
  • Glue for reassembly
  • Magnifying glass or microscope 

 

 

Step 1: Remove the Front Camera

Start by carefully opening the iPhone 12 Mini and locating the front camera module. Use a pry tool or tweezers to remove the front camera. Be gentle to avoid damaging the surrounding components, especially the flex cables and sensors.

 

Step 2: Transfer Face ID Data to the Original Flex Cable

Before proceeding with any repairs, it's crucial to check if there’s a TrueDepth issue. This will determine whether Face ID data needs to be transferred.

Test the TrueDepth system: After removing the front camera, power on the iPhone and check for any Face ID-related error messages or issues with Face ID functionality. If Face ID doesn't work or the system fails to recognize the user’s face, it could be a TrueDepth issue that requires data transfer.

If TrueDepth is faulty, transfer the Face ID data:

    • Connect the original flex cable to a JC programmer (e.g., JCID V1SE).
    • Transfer the data from the old flex cable to the original one.
    • Confirm that the data transfer was successful. Without this step, Face ID will not function when reassembled.

 

 

Step 3: Cut the Brackets Holding the Dot Projector


Once the front camera and flex cable are removed, you'll find small brackets securing the dot projector.

  • Use a small drill or cutter to carefully remove these brackets.
  • Be precise here—cutting too deep or too close can damage the dot projector, which is crucial for Face ID.

 

 

Step 4: Separate the Dot Projector from the Crystal


Next, separate the dot projector from the crystal housing:

  • Heat the assembly with a hot air rework station set at 175°C with an airflow of 50.
  • Focus the heat on the area where the dot projector is attached to the crystal, warming it evenly.
  • Once heated, gently use a fine blade to separate the dot projector from the crystal. Be very careful not to crack or break the crystal during this step.

 

 

Step 5: Desolder the Dot Projector from the Flex Cable


Now that the dot projector is separated, the next step is to desolder it from the flex cable:

  • Use a soldering iron to carefully remove the dot projector from the old flex cable.
  • Clean the back of the dot projector using flux and soldering wick to remove any remaining solder.
  • Ensure the surface of the dot projector is flat and clean for the next step.

 

 

Step 6: Remove the IC (Integrated Circuit) from the Dot Projector


The IC (Integrated Circuit) on the dot projector is essential for Face ID functionality. You’ll need to remove it carefully:

  • Use your soldering iron to heat the solder pads where the IC is attached.
  • Gently lift the IC from the dot projector once the solder has melted.
  • Be cautious not to damage the surrounding components or pads on the dot projector during this process.

 

 

Step 7: Bridge the Pads and Solder the IC onto the New Flex Cable


Once the IC is removed, you’ll need to bridge the pads and solder the IC onto the new flex cable:

  • Use thin soldering wire to bridge the small pads where the IC was removed from.
  • Carefully position the IC onto the new flex cable and solder it in place, ensuring all connections are secure.
  • Double-check each connection to make sure there are no cold or loose solder joints.

Tip: A magnifying glass or microscope will help you maintain precision when working with such small components

 

 

Step 7: Reassemble the Dot Projector with the Crystal


Once you have successfully transferred the IC and soldered it to the new flex cable, it’s time to reassemble the dot projector with the crystal:

  • Carefully align the dot projector with the crystal.
  • Alignment is critical at this stage—double-check the position to avoid misalignment, which can cause Face ID issues.
  • Once aligned, secure the dot projector to the crystal using a strong adhesive or glue. Allow it to set fully before proceeding.

 

 

Step 8: Test Face ID Functionality


Before fully reassembling the iPhone 12 Mini, test the Face ID functionality to ensure everything is working correctly:

  • Temporarily connect the flex cables to the iPhone and power it on.
  • Test Face ID to make sure it functions as expected.
  • If Face ID isn't working, double-check your data transfer, IC soldering, and alignment.
  • Once Face ID is confirmed to be working, reassemble the iPhone 12 Mini.

 

 

Pro Tips for Success:

  • Focus on Alignment: Misalignment between the dot projector and the crystal is one of the biggest challenges during this repair. Be patient and double-check the positioning before securing the components with glue.
  • Maintain Cleanliness: A clean workspace is crucial when working with sensitive electronics. Dust and debris can interfere with soldering and alignment, so be sure to keep your tools and components free of dirt.
  • Practice First: If you're new to this type of repair, consider practicing on a damaged or non-functional device first to build your confidence and skill.

 

 

Here's a Detailed Video On Fixing The iPhone 12 Mini Face ID: