How to Fix iPad Air 2 Touch Screen Problem

Have you ever met iPad touch screen problem before? We are going to fix a iPad Air 2 with the same fault, it can be reboot in a proper way, the only problem is that the screen cannot work at all, how to fix the frustrating problem?

1. First of all, measuring the iPad touch power supply, we can't find PPVDD_STINGER_BOOST voltage.

PPVDD_STINGER_BOOST bitmap position of iPad as shown in picture 8-8-1.

Example8-8-1

PPVDD_STINGER_BOOST principle diagram of iPad as shown in picture 8-8-2.

2. Diode value of L4001 inductor cannot be found when measuring with multimeter. As shown in figure 8-8-3.

3. In order to ensure the stability of the iPad, after replacing the L4001, by the way, D4001, C4014 and C4017 are replaced together. As shown in picture 8-8-4.

4. Connect and reboot the iPad Air 2 to measure the value again, we find PPVDD_STINGER_BOOST shows 20V voltage now. As shown in picture 8-8-5.

Example8-8-5

5. Finally, the touch function is tested as normal and the iPad motherboard is repaired successfully.

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