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Solution: iPhone 6 Activation with WiFi Fault

We're fixing the iPhone 6 today, the customer described the failure as WiFi can't be turned on. After removing WiFi, the activation interface appears. Connecting to the test, we found that the iPhone 6 WiFi chip was not installed, the data cable was not installed in boot-up activation mode, and when we connected to the AISI assistant, we found a serial number with no baseband.


After a period of use, it enters the activation mode again, usually based on our usual maintenance experience of baseband power output short circuit. Considering WiFi removal, the GPS power amplifier associated with the WiFi edge has a voltage output baseband power.

Measure with a FLUKE digital multimeter, it's PP_LDO13 as shown in picture.


After eliminating the short circuit, the result is that the C5129 is broken, the resistance is back to normal, connecting Aisi assistant we find the baseband out. Using Ace assistant to skip WIFI, activate the backward menu again and use it properly.


Install it on a WIFI and find it still hard to turn on. After borrowing 1.8V to reset, it is found that the WIFI address appears, but still can not turn on it. Use the Digital Storage Oscilloscope to measure the 32K clock test point we found no waveform.

The clock is from the main power source, so we replace the main power to measure again.

Now the waveform appears, test WIFi again, the fault is successfully solved.



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