Solution: iPhone 6P receiver and light sensor not working during calls

When we answered the call on iPhone 6 Plus, there is no sound from receiver, and the light sensor is not working during the calls.  What's trouble? Usually, the receiver, the iPhone tail plug cable and the iPhone audio IC all will cause this problem, here is the solution to fix it.

Frist, disassemble the iPhone 6 Plus by phone opening tools, remove the iPhone display assembly.

 
Replace the new iPhone receiver. Use tweezers to remove the receiver, and then install the new one. 

Install the iPhone and test it, the problem still the same.

Disassemble the iPhone, carefully take out the iPhone motherboard. 

Replace the iPhone tail plug flex cable, and then install the new iPhone tail plug cable.

Install the iPhone and test it, the problem still the same.

Now,we need to check iPhone audio IC.

Remove the iPhone motherboard, put it under the microscope to check iPhone audio IC
U090. 

Use QUICK 861DW hot air rework station to remove the iPhone audio IC, and then install the new iPhone audio IC to the motherboard.  

 

Install the iPhone, and test it again, now the problem has been solved, all functions works perfectly.

Solved: iPhone 6 white Apple failure (large current)

A customer sends an iPhone 6 that needs repairing, this iPhone 6 has white Apple failure. The fault described by customer is that the iPhone motherboard is deformed,water damaged, layer cracked, fingerprint failure.

Detection

After we received the iPhone motherboard, measure the iPhone motherboard.

Connect iPhone motherboard to the DC power supply, the boot current is large, the failure is iPhone 6 white Apple and large boot current.

Fault Repair

We need to detect the iPhone motherboard carefully, （put it under the microscope to observe, no specific faults found ）

Based on our previously repair experience, when measure the resistance value of the USB by digital multimeter, the resistance value turns down.

Use Titanium Alloy Tweezers to remove the USB IC, the boot current measured is normal, so we replace the USB IC directly.

Test Functions

After replacement, assemble the iPhone 6 and test, all functions are fine.

Repair Guide: iPhone 6S short circuit after booting

A customer sent us an iPhone 6S motherboard, the problem is that the iPhone 6S is short circuit after booting.

After we received the iPhone 6S motherboard, it looks good and never been repaired.

Connect iPhone motherboard to the DPS DC power supply, the current of the beginning tested is 20mA, it's normal.

When the current jumps to 40mA, which means the iPhone power and CPU starts to work. When the current jumps to 10.6mA, which mean the upper was opened.

When the current jumps to 70.8mA, which means the iPhone Nand flash starts to work. When the current jumps to 100mA, which means the CPU starts the I2C data bus, at this time, the iPhone display power IC start working, the Apple LOGO will appear on the iPhone display screen, and then the iPhone backlight start to work. At this time, the current is usually around 300mA.

When the Apple logo appears, the current on the DC power supply screen is constantly jumping，because the iPhone baseband and iPhone WiFi are being started. After the iPhone screen is lit, the current will jump back to 300mA from 500mA.

However, when the current jumps up the second time, the iPhone motherboard is short circuit and turned off. Our preliminary judgment is that the amplifier has a problem.

First to check whether the power supply of amplifier is normal, after testing, every power supply of amplifier is good.

Seems it's complicated, but after thinking, we know that the iPhone amplifier IC and iPhone WIFI IC are the most power consumption parts.

Connect iPhone motherboard to DC power supply to boot it, after few second, the WIFI is overheating, the problem was found.

Heat iPhone WIFI IC by QUICK 861DW hot air rework station, and then use Titanium Alloy Tweezers to remove the iPhone WIFI IC. Now, measure it again, the current is normal, and no short-circuit phenomenon.

Install the new iPhone WIFI IC, remove the iPhone Nand flash, and then use JC Pro1000S to unbind the WIFI.

Finally, install the iPhone 6S, and test it, now the iPhone works properly.

Hardware Repair iPhone 6 Plus WIFI Function Not Working problem

We received an iPhone 6 Plus from our customer, the fault described is that the iPhone WIFI function is not working, because the iPhone WIFI button is grayed. This iPhone was repaired once, but not well, now we are going to repair it.

After weceived the iPhone, first we try some softeare solutions ( restart, reset network setting and so on), it doesn't make any sense. 

Use phone opening tools to disassemble the iPhone 6 Plus, and tthen take out the iPhone motherboard, we found the iPhone WIFI IC is not installed, and there are a lot of solder points fallen off.

Check the WUXINJI bitmap and find out the 32K clock signal pin of WiFi is lost. Bluetooth synchronization control, clock and so on, Bluetooth foot position directly through the iPhone CPU.

Pry the pin and solder the jumper wire, apply some green UV oil. Welding the original WIFI and turn on the iPhone to test, it's gray WIFI too, and the iPhone also stuck. After we replace a new one, the fault is still same.

Disassemble the iPhone again, we suspect the iPhone WIFI IC didn't installed well, heat it by QUICK 861DW hot air rework station, and then use tweezers to press the iPhone WIFI module IC.  

Assemble the iPhone, get into IOS to test the WIFI function, it works well.

Solution: iPhone 6S Screen doesn’t display after booting

 The iPhone 6S screen doesn't display after booting, here is the solution. The iPhone has been hurt by water, it can't be turned on, just shows black screen. The solution as follows.

Use phone opening tools to disassemble the iPhone, and then connect the iPhone to the DC power supply to test the iPhone boot current, the current data tested is normal, which means the iPhone can be turned on smoothly.

Take out the iPhone motherboard, observe it under the Stereo Zoom Microscope, there are small trace of water on the iPhone motherboard. Carefully clean it up.

Observing the iPhone display socket and those inductance resistances around it, we found the FL4220 is virtual welding.

Check iPhone schematic diagram in the WUXINJI Dongle, so we can know the position of the FL4229.

Now, use Titanium Alloy Tweezers to remove the FL4220, and the use QUICK 861DW hot air rework station to short connect it.

After connection, measure the iPhone, all data test are normal. So, assemble the iPhone to test, the iPhone screen has display now. Test other functions on iPhone, all works well!