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iPhone 6 Frequently no Service, What Happened?

When using the iPhone6, there may be occasions when there is no service. So how do you solve this problem? 

Received a faulty iPhone 6 phone from the customer, customer description: often no service, display search signal on the iPhone display. 


Detailed description When the iPhone is in the no-service state, there is no IMEI after dialing *#06#. According to our previous repair experience, it may be due to the RFFE1 and RFFE2 bus of the iPhone baseband causing this iPhone to have no service failure.

   


By examining the iPhone schematic with WUXINJI Dongle, we found that the two sets of buses are the various ICs that the baseband CPU uses to manage the signal portion. For a lost iPhone, the circuit of RFEE1_DATA to the U1 pin is usually disconnected. 

Use the phone opening tool to remove the iPhone and remove the iPhone motherboard. Then use the QUICK 861DW hot air rework station to heat the iPhone baseband, then remove it with tweezers and then jump from the soldering U1's pin to the back side test point. figure 1 Then apply some green UV oil. 

    


To make it solidify, we use an ultraviolet light and then install the iPhone baseband to the iPhone's motherboard.

Finally, assemble the iPhone, turn on the power and enter the IOS system for testing. The result shows that the iPhone signal works normally. After a few days of use, the iPhone also shows a service. Mobile phone repair was successful.

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