Solution: SIM Card can’t be recognized on iPhone 6S

The SIM card can't be recongnized on iPhone 6S,we re-installed SIM card many times, but it still won't be recongnized. Now, we need to check the interior of the iPhone 6S.

Use phone opening tools to disassemble the iPhone 6S, take out  the iPhone motherboard and put it under the Trinocular Stereo Microscope to check, we found the iPhone baseband power was repaired, because there are a lot of solder patse.

Use digital multimeter to measure the voltage of each pin of the socket at the moment of power-on, all the SIM-RST SIM-CLK SIM-DATA have instantaneous voltage, only SIM-VCC does not.

According to past repair experience, there are 2 problems in the power supply of SIM card, one is baseband power supply problem, the other one is capacitance resistance problem.

The baseband power supply has been repaired, without considering power supply. It should be a small capacitor or a small resistor problem.

By checking the WUXINJI circuit diagram, it is found that the small capacitance and the resistance are under the shield cover, carefully cut off a part of the shield, and observe the small capacitance under the Trinocular Stereo Microscope. It is found that the color of a small capacitor is a bit different, so we remove the damaged one by QUICK 861DW hot air rework station.

Now, the power supply pin of the SIM card is measured again by digital multimeter, the voltage is normal.

Reinstall the iPhone 6 and insert SIM cart to test, the card can be recognized now. 

iPhone 6 No Display Repair- Get solution here!

A customer sent us an iPhone 6 to repair, the fault described is iPhone 6 won't turn on. But after we test it, the real problem for this iPhone 6 is no display after boot. We can repair it!

After received the iPhone 6, use phone opening tools to disassemble it, and then take off the iPhone 6 logic board.

Observe the iPhone logic board, the iPhone logic board looks good, no trace of water-damaged or traces of external pressure are found.

Connect iPhone logic board to DPS DC power supply to test it, the boot current tested is normal, but the iPhone LCD screen still no display, always keep black.

Measure the resistance value of the J2019 by digital multimeter, the resistance value is normal. Now, measure the voltage, there are no positive and negative 5.7V, and we suspect that the U1501 is damaged.

Remove the U1501 by Titanium Alloy Tweezers, and then install the new one to the iPhone logic board. After replacement, measure it again, but the 5.7V still can't be measured, we think the boost has some problem.

Check iPhone schematic diagram in the WUXINJI Dongle, from the iPhone schematic diagram, we need to replace the C1529 and C1502. After replacement, measure the iPhone again, now the data is normal.

Assemble the iPhone, turn on iPhone to test, now the iPhone LCD screen displays normally, the repairs end!

Solved: iPhone 6 No display with logic board repairing

We received an iPhone 6 need to be repaired, the problem is that the iPhone 6 has no display when it is turned on.

First check whether the iPhone display socket has water damaged or virtual welding problem, after removing these problems, measure the resistance value of the socket by digital multimeter.

After measurement, we found the display socket 12 pin doesn't have resistance value. Check if the connected c2001 capacitance and fl2034 inductance have corrosion and virtual solder problems, the fl2034 inductance measured are no resistance value.

The fl2034 inductance passes through the U2403 6 pin tube and then to the CPU. Using a digital multimeter to measure the iPhone touch screen control IC U2403 of the corresponding bottom pins, the data tested are normal. So, we can eliminate the CPU problem. In this case, we need to solder jump wire.

Use QUICK 861DW hot air rework station to remove the cover, and then solder a jumper wire from the 6th pin of u2403 to a measuring point next to the screw hole，and then solidify it with green UV oil.

Install the iPhone and test it, the failure has been solved.

How to repair iPhone 7 Plus vibration function unavailable issue

 The iPhone 7 Plus has some problem, it won't vibrate. How to repair it? Keep reading.

Disassemble the iPhone 7 Plus by phone opening tools, and then remove the iPhone logic board.

Check iPhone logic board under the Stereo Zoom Microscope, no obviously scars. 

Measure the iPhone logic board by multimeter, the data tested is normal,but the iPhone 7 Plus still won't vibrate.

Open the WUXINJI Dongle to check the iPhone schematic diagram, analysis the iPhone vibration IC working principle.

Frist,try to replac the iPhone vibration IC, after replacement, the iPhone 7P vibration function still is unavailable.  

Carefully check iPhone vibration IC working principle again, we found the M2800 is damaged. Use QUICK 861DW hot air rework station and Precision Titanium Alloy Tweezers to replace the M2800.

After replacement, install the iPhone 7P, get into IOS to test the iPhone, now the iPhone vibration fucntions works properly. The issue has been solved.

Hardware solution for iPhone 6 4013 error

A customer sent us an iPhone 6 to repair, the fault described is that the iPhone 6 reports 4013 error when flash it with iTunes. 

Frist, connect iPhone 6 to the computer with iPhone lightning cable, and then use iTunes to flash iPhone again, we found the white Apple logo appears properly but can't enter the normal mode and reports unknown error 4013.

The iPhone 6 reports 4013 error is usually caused by iPhone Nand flash or CPU problem. In this case, frist we need to remove the iPhone Nand flash, and then use iTunes to re-flash the iPhone, finding that the iPhone can enter the normal mode and report 40 error, seems it's the iPhone Nand flash problem.

The iPhone 6 reports unknown error 40 is normal thing when the iPhone Nand flash is not installed. Use JC Pro1000s Nand problem to read the data of the original iPhone Nand flash, and then write this data to the new iPhone Nand flash, but we found the data of the iPhone Nand flash couldn't be read.

 

Therefore, we can only use the iPhone IMEI to find the original iPhone Nand flash SN, BT and WIFI address. After find out this information, use iPhone Nand test fixture to write these data to the new iPhone Nand flash, and then install Nand flash to the iPhone logic board by QUICK 861DW hot air rework station.

Assemble the iPhone 6, re-flash the iPhone via iTunes, the flash process goes well. Activate iPhone and test it, all functions are working properly, the repairs end!