iPhone 12 Pro Max speaker no sound repair

iPhone 12 Pro Max speaker no sound repair

iPhone 12 Pro Max speaker has no sound. It is found that it is caused by coder power amplifier chip. The fault is repaired after replacement.

Machine model: iPhone 12 Pro Max
Customer Description: there is noise from the bottom speaker
Test results: the mobile phone can be turned on, all functions are normal, and the bottom speaker has noise.
Fault analysis: all functions of the mobile phone are normal, only the bottom speaker has noise, which proves that the signal line from the bottom speaker to coder is faulty.
Open Xinzhizao Soft, find the marked drawing of iPhone 2 Pro max, and find the bottom speaker FPC BTB connector according to the drawing.

iPhone 12 Pro Max speaker no sound repair Figure 1.

Open Boardview of iPhone 12 Pro max, find the sub FPC BTB connector, and measure the motherboard according to the reference diode value.

iPhone 12 Pro Max speaker no sound repair Figure 2.

After measurement, it is found that diode value of BTB connector sub connection coder power amplifier is abnormal.

iPhone 12 Pro Max speaker no sound repair Figure 3.

After replacing coder power amplifier chip, the fault was repaired.

iPhone 12 Pro Max speaker no sound repair Figure 4.