The Wi-Fi switch cannot be turned on. The Wi-Fi MAC address can be found in “about iPhoneâ€
Repair Process:
First teardown iPhone and then measure the diode data of Wi-Fi chip and PCIE bus communicating through CPU. The test point of PCIE bus is on the coupling capacitance that is on the right of U1501, as shown in picture
The Wi-Fi chip cannot be removed when the diode data of PCIE bus is being tested. Otherwise, the diode data to Wi-Fi can be infinite. The circuits between Wi-Fi solder pad and the 6 capacitances often disconnect. If that happens, measure the ends of capacitance. The n ormal diode data is about 350 on one end and 500 on the other end.
If the iphone backlight diode data of the 6 capacitances is normal, then remove the Wi-Fi chip to measure the diode data of every pin of solder pad. If all the data is normal, first use a normal Wi-Fi chip to replace the old one and turn on iPhone to test. If the trouble is the still the same, it is caused by unqualified Wi-Fi working condition.
After checking the function diagram, we find that the voltage of Wi-Fi clock is not measured. Remove the Wi-Fi and then measure the clock, there is not 0.9V voltage. The frequency of the Wi-Fi clock is 32.768kHz, which is made by the Y1200 crystal oscillator. Then Y1200 crystal oscillator transmits it to power Drive control chip . Power chip transmits it to Wi-Fi chip. Considering the iPhone is dropped, the crystal oscillator may be broken because it is not anti-shock. Replace the old Y1200 crystal oscillator. The Y1200 material object is shown in pi cture
After the replacement, turn on iPhone and test. Wi-Fi switch can be turned on normally and Wi-Fi signal becomes normal. The trouble is removed.
Repair Process:
First teardown iPhone and then measure the diode data of Wi-Fi chip and PCIE bus communicating through CPU. The test point of PCIE bus is on the coupling capacitance that is on the right of U1501, as shown in picture
The Wi-Fi chip cannot be removed when the diode data of PCIE bus is being tested. Otherwise, the diode data to Wi-Fi can be infinite. The circuits between Wi-Fi solder pad and the 6 capacitances often disconnect. If that happens, measure the ends of capacitance. The n ormal diode data is about 350 on one end and 500 on the other end.
If the iphone backlight diode data of the 6 capacitances is normal, then remove the Wi-Fi chip to measure the diode data of every pin of solder pad. If all the data is normal, first use a normal Wi-Fi chip to replace the old one and turn on iPhone to test. If the trouble is the still the same, it is caused by unqualified Wi-Fi working condition.
After checking the function diagram, we find that the voltage of Wi-Fi clock is not measured. Remove the Wi-Fi and then measure the clock, there is not 0.9V voltage. The frequency of the Wi-Fi clock is 32.768kHz, which is made by the Y1200 crystal oscillator. Then Y1200 crystal oscillator transmits it to power Drive control chip . Power chip transmits it to Wi-Fi chip. Considering the iPhone is dropped, the crystal oscillator may be broken because it is not anti-shock. Replace the old Y1200 crystal oscillator. The Y1200 material object is shown in pi cture
After the replacement, turn on iPhone and test. Wi-Fi switch can be turned on normally and Wi-Fi signal becomes normal. The trouble is removed.
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