Apple Pencil Wavy lines after a screen replacement

After replacing the screen on some iPads, users might notice that when they try to draw straight lines with an Apple Pencil, the lines appear wavy or jittery. This issue often arises because the screen’s touch sensor and the Apple Pencil are calibrated to work together based on a specific screen serial number. This affects the iPad Air 4, iPad Air 5, iPad Pro 11′ 3rd Gen and above.

Here’s a detailed explanation:

  1. Screen and Touch Sensor Calibration: The iPad’s screen and touch sensor are precisely calibrated at the factory to work seamlessly with the Apple Pencil. This calibration ensures accurate detection of the pencil’s position and pressure, resulting in smooth and straight lines when drawing.
  2. Screen Replacement Impact: When the screen is replaced, the new screen may have a different touch sensor calibration. If the iPad does not recognize the new screen’s serial number, it may not properly adjust the calibration, leading to issues like wavy or jittery lines.
  3. Software Solution: Apple has introduced new software that allows technicians to copy the original screen’s serial number to the new screen. This process ensures that the iPad recognizes the new screen as if it were the original one, maintaining the precise calibration needed for the Apple Pencil.
  4. How we do it:

  • Read Original Serial Number: Before replacing the screen, the technician reads the serial number of the original screen.
  • Replace Screen: The technician then replaces the screen with the new one.
  • Write Serial Number to New Screen: Using Apple’s software, the technician writes the original screen’s serial number onto the new screen.
  • Calibration Verification: The iPad now recognizes the new screen with the correct serial number, ensuring that the touch sensor calibration is accurate.

  1. Outcome: By copying the screen serial number to the new screen, the touch sensor and Apple Pencil calibration is preserved, resulting in smooth and straight lines when drawing, just like with the original screen.

This software solution effectively addresses the issue of wavy lines caused by screen replacements, ensuring that the Apple Pencil functions correctly with the new screen.

We now have the correct software to be able to copy the serial number from the old screen to the new screen so you will be bale to draw straight lines with your iPad Pencil.

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