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Repair Solution: iPhone 6S No Ringtone

We received a iPhone 6S with ringtone function fault, how to test and repair step by step? Let's check in the article!
 

Failure analysis: first of all, we install the iPhone 6S motherboard to test whether there is any vibration without bell, because ringing and vibration are closely related. 

It is found that the vibrating bell is not entirely absent, there a little sound just click it, then the sound disappeared at soon.
 
For this kind of situation, we can give priority to check the iPhone 6S bell boost in this respect, observe under the LED Stereo microscope, we found the L3700 bell boost a little blackened. 

The picture are shown as as follows:



Solution: Replace a new L3700 coil, install the iPhone to test again, the ringtone fault is perfect solved now! (general coil without direction and model difference, can be commonly used)
If you want to get more cell phone repair solutions, contact us on www.vipfixphone.com

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