Fixed: iPhone 7P camera is unavailable

The iPhone 7 Plus rear camera is unavailable, but the front camera works good, what's going on? How to fix it? 

Fristly, diasassmeble the iPhone 7 Plus, remove the iPhone rear camera, install the new one, and then test it, the iPhone rear camera still not working. 

Disassemble the iPhone, take out the iPhone motherboard, we found the iPhone WIFI IC and iPhone audio IC was repaired before. As we know, the iPhone camera power supply transfer tube on the WIFI IC are easy to virtual weld. So, we remove it, and then re-weld it, but the iPhone rear camera still not working.

Use digital multimeter to measure the grounding resistance value for iPhone rear camera J3001 and J4501, the data is normal. And the power supply for camera socket tested also is normal.

Measuring the I2C bus on J3001 and J450，when measured the J3001 2 pin, finding that it only has 0.4V voltage, but in the normal case, the normal voltage of I2C bus should be around 1.8V. 

Open the WUXINJI Dongle to check iPhone schematic diagram, this I2C bus via safety resistor R3301 to M2600, pull-up supplied by R4604 resistor.

Combine iPhone bitmap to find R4604 resistor, one side of the resistance value measured of R4604 is normal, the other side is 0.4V, which is obviously wrong，we suspect the pull up resistor is damaged. 

With the help of the QUICK 861DW hot air rework station and tweezers, we replace the pull up resistor, and the measure it again, now the both sides voltage of resistor are back to normal.

Install the iPhone, get into IOS, tap iPhone camera icon, the iPhone rear camera is available now, switch it to front camera, aslo works properly. 

iPhone Short circuit- Repair iPhone 7 won’t turn on failure

The iPhone 7 short circuit and causes iPhone 7 won't turn on. The trouble details are that the iPhone 7 fell into water, after we clean up the water, press the power button, it doesn' t response, we need to repair it. 

For water damaged iPhone, first we need to check the exterior of the iPhone, generally，the part that have been in the water is easy to damage. After appearance has been detected，we need to connect it the DC power supply to check the iPhone status. 

Connect iPhone motherboard to DC Power supply, no leakage, press the iPhone power button, the current jumps from 200mA, this failure mostly is caused by power supply short circuit, it also can be measured, just check the several power supply circuits that is output by the main power supply.

After measuring these power supply circuits, we can identify where the short circuit part is.

When measured the PP3V0_TRISTAR_ANT_PROX this signal, we found it is short circuit. This signal is reached to these place and USB, we can check it on iPhone 7 schematic diagram.

Directly remove the USB, and then measure the iPhone data again, but the iPhone still short circuit.  For water damaged iPhone, we need to observe iPhone exterior more carefully, and the customer has been repaired this iPhone before, put iPhone motherboard under the Trinocular Stereo Microscope and then continue to observe it.

We found there is a damaged chip, it's probably the damaged chip that caused the PP3V0_TRISTAR_ANT_PROX to short-circuit. Remove the inductance attached to it， after remove this inductance, we found the resistance value of PP3V0_TRISTAR_ANT_PROX is back to normal. Now, install the USB.

Press the iPhone power button, now it is normal, but the iPhone always stuck on white Apple logo and won't enter the IOS system. The current tested by DC power supply is to 2A and then down to 200mA and then stop, we suspect it is caused by iPhone audio problem, the current is normal, but it down to 200mA and won't move. 

After detected, there's damage on both sides of the audio, use QUICK 861DW hot air rework station to remove the iPhone audio IC and replace the new one.

Finally, press the iPhone power button, the iPhone is turning on properly,  after get into IOS, test all functions on iPhone, they works well! The iPhone 7 won't turn on failure has been repaired!

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!