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Fixed: iPhone 5 Audio Part Repair

Are there any problems on the audio part of your iPhone? If you are cell phone repair professionals, you must know that the iPhone 5 audio part is composed of audio IC-U21 and ringtone amplifying U19. We need to figure out where to start repairing so we have to test carefully to the specific parts. Here we'll introduce the details in the article!




The receiver signal RCVR_P RCVR_N in the normal call mode is sent out of U21 through the inductor FL51 FL52 and sent to the receiver flex cable interface J1. The inductance FL51 FL52 is easy to corrode and damage the receiver, which can be solved by short connection. The iPhone microphone signal is shown in picture 1, you can check on WUXINJI circuit diagram.


iPhone 5 common audio fault is usually caused by water, resulting receiver function failure, inline corrosion or solder joint or FL51, FL52 pseudo soldering or shedding cause no receiver! Of course, before the repair we should first exclude the receiver flex cable is not a problem!

Artificial disassembly damage results in no voice from the other side!
When the WiFi module is disassembled, the audio IC will be blown or short circuited.
If the recording is not normal, or there is no sound, it is usually the audio IC pseudo welding, you can solve by reinstall the audio IC. This audio IC is much easier than other IC. Before the audio IC is removed, the power supply of the audio IC must be checked in place. If the DC power supply measurement is normal, then the audio IC can be taken off.

One is 1.8V, the other is 3.2V, as shown in picture 2.


VCC_MAIN supplies output 3.2V voltage to audio IC--U21 through U20. If 3.2V is not detected in C422 by Fluke digital multimeter, then check U20 small glass IC.

Another situation is normal recording but silent calls, reinstall audio IC fault is still caused by baseband CPU or baseband power false welding!

Another situation is the sound of calls. There is no ringtone. It is the problem of ringing IC--U19, which can be replaced or reinstalled. Of course, the power supply must be checked before disassembly.

In addition, L4 is easy to fall out of welding and damage. After checking L4 and power supply are normal, resolutely reinstall or replace U19.

If you have any other problems for cell phone repair , please contact on www.vipfixphone.com

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