iPhone 13 Pro Max Screen Failure for repair

Machine model: iPhone 13 Pro Max

Malfunction: the mobile phone screen is out of order.

Maintenance process: the mobile phone can be turned on, but the screen fails, and the customer swiped the phone.

iPhone 13 Pro Max screen failure figure 1.

Disassemble the screen, replace a test screen or do not touch it, and check the bit map to show whether the bus is ol through the coupling capacitor. Other values are normal. Find the display part of the power supply, and there is just an empty corner in the middle of the seat. The power supply must be locked on the screen before it can be measured. According to experience, it may be that a power supply tube is broken and needs to be shorted or replaced and layered.

iPhone 13 Pro Max screen failure figure 2.

Simply layered and easy to measure the voltage, I found an ID board to measure the voltage again. When testing the fault board, it was found that there was a power supply chip that didn’t output power supply. The ID board measured 5V here. When the power supply was disconnected, it was found that this circuit was short-circuited. When the large capacitor was removed, it was found that it was not short. This circuit power supply should be the chip’s own boost power supply, and a boost capacitor should be replenished.

The test power supply is available, and the touch is normal when it is attached. Because of the ID account, the customer has to activate it himself, and the fault is perfectly repaired.