Got the iPhone 6S which carried the 4014 error , according to the description which comes from its mater, the fault occurred after he flash it and still kept in the DFU Mode.
After we check the sources fault, we decided to disassemble it to check the iPhone motherboard, the iPhone Nand flash on this motherboard has been repaired, and when check it under the microscope, we can see that the iPhone NAND flash damaged.
Remove the iPhone Nand flash and measure its diode data, it is normal. Put Nand flash into the WL PCIE Nand test programmer to test it, unsurprisingly, the NAND flash is damaged.
Picture 14-2-1
Replace the new iPhone Nand flash and flash it again, the fault still exists. As we know, the iPhone 6S and later iPhone reports iTunes error 4014 mostly caused by nand flash and baseband issues. However, after measuring, we know that the iPhone Nand flash is good, so now the problem is iPhone baseband. Measure the diode data of baseband power LDO part and S1-S5 power supply, all is normal.
Picture 14-2-2
Flash it again, test the S2 and S4 when the White Apple logo appears, there is no power in either of these places. Since S2 and S4 have no power, it is possible that the baseband power supply does not work and then can't output power. Remove the baseband power, and then use Fluke 15B+ Digital Multimeter to measure it, we found the 55 pin is to ground.
Picture 14-2-3
Picture 14-2-4
55 Pin connected to the 19.2M clock, put iPhone motherboard under the VGA Camera 7-45X Trinocular Stereo Microscope to observe the 19.2M clock.
Picture 14-2-5
19.2M clock with C3501_RF capacitor grounding end connected together
Picture 14-2-6
After we finish the above step, we deal the baseband clock well and then flash it again, we can see the phone can run normally, the fault disappeared. The repair is success.
No comments:
Post a Comment