Professional Cell Phone Repair Guide

The iPhone 6 display is black after replacing LCD. After checking, the diode data of display socket is normal and all power supply for iPhone display IC  output is normal. Testing by  DC power supply , we find the iPhone current is abnormal. When press the iPhone power button, the boot current is obviously large. The current reached 100mA when press the power button. After remove the display tube, the current still the same, which means there is a short circuit. Measure the voltage output of each circuit of power supply with Fluke 15B+ Digital Multimeter , then surprised to find that there are really short circuit places. LD010 is short circuit; we suspect that the filter capacitance on the circuit has been penetrated. After remove the iPhone power control IC , we found it is ground short circuit. Open the WUXINJI Dongle  to check the iPhone schematic circuit, we found that this circuit is the display card image transmission MIPI data bus power supply. CPU brea...

The iPhone 6 Plus fault is that the iPhone flashlight cannot be turned on, and the iPhone rear camera   won't open either. But the iPhone front camera is normal. How to repair this kind of fault? Generally, if the iPhone rear camera won't turn on, then the flashlight also cannot be turned on normally. As long as one side is abnormal, it can cause no reaction. After check the iPhone circuit diagram on WUXINJI Dongle , we know that they all communicate with the CPU through the I2S_ISP_TO_RCAM_SCL_I2C_ISP_BI_RCAM_SDA bus. As long as one fails, both of them cannot be used. Use JM-P01  Essential Phone Repair Toolkit to remove the iPhone motherboard, and observe it under the 7-45X 180X Stereo ZoomMicroscope , we found the U3200 chip had traces of moldy by water. With the help of QUICK861DW  and Precision TitaniumAlloy Tweezers , we remove the chip smoothly and quickly. And then we found out that the U3200 chip 4-pin pp_vcc_main powered pin had corrode...

We are going to fix an iPhone 6 device today, the iPhone 6 signal keeps searching state after booting, there is no baseband in local setting, and no series number shows up when dialing *#06# serial number. We find the iPhone 6 LCD (has been replaced once, this kind of situation is preliminary determined for baseband CPU false welding, it is relatively common situation on iPhone 6 and iPhone 6P. Anyway we need to test first! From the simple start, measuring the single iPhone 6 motherboard  baseband power supply, first measure the main power supply 4.2V (C3221_RF). Then testing basebnd output voltage of power supply on C3262, C3252, C3259, C3256, if there is a voltage without first measuring resistance, if resistance is normal, then replace normal baseband power test; if four of them are simultaneously without resistance, then you need to reinstall the baseband CPU. There is a small glass tube base strip above the baseband power supply, it must be noticed when the main ...

We are going to repair an iPhone 6 Plus device with fingerprint, front and rear camera fault, the customer described the iPhone black touch IC   was repaired before , it is possible to put the back of the component virtual weld. Anyway, we need to fix it step by step. First of all, measure the diode data of rear camera adapter with Fluke 15B+ Digital Multimeter , no exceptions found. Then measure the rear camera power supply. Measure the main camera 1.8V and 1.2V power supply, when we measured the 2.85V power supply, we found that it had no power. Check the iPhone 6 Plus schematic diagram on WUXINJIDongle   to trace the 2.85V source. We found that the 2.85V was converted from the main power supply through U2301 . During the repair process, short connection A1 and A2 pin can quickly determine if 2.85V power is causing the iPhone camera  not working. After short connect A1 and A2 pin, get into IOS to test the iPhone rear camera, it can be turned on n...

According to customer's description, the iPhone 6 WIFI cannot be opened and the WiFi icon is gray during the normal using process, we judge that this kind of situation should be the  iPhone 6 WIFI module  can't work. How to fix the WiFi fault in details? Test whether the main power supply 4.2V has been delivered on C5202_RF, if not, it can be supplied from any place with main power supply, or directly replace WIFI module. Before disassembly, we need to do some protection to avoid blowing other chips. The WIFI module is surrounded by glue. We must first preheat and remove the glue, and pay attention to small components, especially small resistors. you must to solder it again if some of the components are lost. The WIFI module on line is relatively thin, do not use solder iron  back and forth on iPhone solder pad, testing resistance again after cleaning. As shown in figure 14-5-3, the lower right-hand corner is easy to break, and the normal is infinite. Th...