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The Best Solution to Fix iPhone 6 Plus SIM Card Can't be Recognized

Got an iPhone 6 Plus from one of our customers, the main fault is described that the SIM cart can't be recognized. Why this happens? Let's learn how to test and repair it in detailed steps, hope it will help!


Generally , the same fault is caused by damaged cell phone SIM card slot. First we are going to measure the SIM card slot to the ground value with digital multimeter. We found that the SIM card slot 1 pin PP_LDO5 is short circuit to the ground.


Disassemble the iPhone with iPhone 6 Plus opening toolkit, check the iPhone 6 Plus bitmap on computer with WUXINJI Dongle, it shows that PP_LDO5 is sent from the baseband power supply to the baseband CPU, SIM slot 1 pin, capacitor C3100_RF and the diode DZ3101_RF.


It is not very likely that the base band CPU gets damaged, so we test by removing baseband power supply, it is still short circuited after that. Then we try to remove the capacitance C3100_RF, now the ground resistance is normal now.

It seems that the problem is solved, restall the baseband power and turn on the iPhone6 Plus to test, it can identify the SIM card normally.

After activation, the function is tested all normal, the fault is successfully repaired.

More details about professional iPhone repair, please contact on www.vipfixphone.com

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