Fix iPhone 6P WIFI cant open and the WIFI address is unknown

The present situation is iPhone 6P Wi-Fi cannot be open and the Wi-Fi address in “about iPhone” displays “unknown”. You must be confused, because there are many reasons to result this problem. Dont worry, Vipprog can find the reason for you and solve the problem.

Firstly, boot test phone and we can found that there is not any icon in “settings”, as shown in picture 1-31

Secondly, disassemble the iPhone, we found the Wi-Fi chip has been replaced and there are enameled wires under solder pad. Therefore, the improper enameled wires and unqualified working condition may cause the trouble. Remove the Wi-Fi chip directly and measure the diode data of each pin on solder pad. Comparing with normal motherboard, the measured data is normal. After removing Wi-Fi, the measured diode data of PCIE bus is infinite. We can only measure whether the circuit is connected between PCIE bus (as shown in picture 1-32) and coupling circuit C0703, C0704, C0705, C0706, C0720, C0721 (as shown in picture 1-33).

Thirdly, we find the circuits between solder pad and coupling circuit C0704, C0705 are open circuits through measurement. After checking the PCB circuit diagram, we find the circuits between solder pad and C0704 and C0705 will pass PP3169_RF and PP3166_RF, as shown in pictur e 1-34 and 1-35. Then directly connect solder pad and test point with enameled wires, then paint UV Solder Resist, as shown in picture 1-36 and 1-37. Reassemble Wi-Fi chip and test after power on. The Wi-Fi address still displays “unknown”. 

Fourth, remove Wi-Fi chip again and measure the diode data of all pins on solder pad. We find the previous repaired places still in breakage. It connects or disc onnects sometimes. In PCB circuit diagram, find the resetting pull-down resistance R0719, as shown in picture 1-38. Then directly place enameled wire from resetting pull-down resistance, as shown in picture 1-39.

Finally, reassemble Wi-Fi chip and test after power on. “About iPhone” displays Wi-Fi address. The reason is found and the problem has been solved.