Solution: iPhone 7 Plus Screen Half Dim Problem With PCB repairing

After powering the iPhone 7 Plus,  it’s found that the iPhone 7 Plus screen half dim and half bright. We restarted the iPhone 7 Plus, but the problem still exist. So strange, is it the iPhone screen problem or PCB problem? After testing, we confirmed it’s caused by the problem on the iPhone motherboard. Here is the solution.

professional iPhone repair tool

Power down the iPhone 7P, disassemble it, and replace the iPhone display screen with the new iPhone display, assemble it and test it, but the iPhone screen still displays in half dim.

Disassemble the iPhone 7 Plus again, take out the iPhone motherboard, observe it under the Trinocular stereo microscope, it looks good.

Test the iPhone 7P via DC power supply,  press the iPhone power button, the the iPhone is lit up and  the Apple logo appears. We can see that the right side of the screen is darker than the left side. From this, it is judged that the failure may be related to the iPhone backlight circuit.

Use digital multimeter to measure the backlight relevant pins on the display connector J4502, the data measured is abnormal.

Open the WUXINJI Dongle to check the iPhone schematic diagram, you can see that the voltage outputted by iPhone backlight IC U4601 pass through C4602, FL4601 and C4605 and then reach to the J4502 pin 45 .  So, we need measure the C4602.

After measurement, the data is normal. Now we suspected that abnormal value of Pin 45 is probably caused by open-circuited condition of its relevant circuit or malfunction of the display connector J4502. Check J4502 carefully and we find that Pin 45 is virtual welded.

Use QUICK 861DW hot air rework station to remove the J4502, and then use digital multimeter to measure the diode data of Pin 45 again,  now the data tested is normal. Install the good J4502, the data measure also is normal.

Assemble the iPhone 7 Plus, power on iPhone,  now the iPhone 7 plus screen displays normally, the brightness  is balanced.

 

 

 

 

 

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Touch Failure: iPhone 6 Touch Function is damaged by dropping

The touch failure is one of the most common problems that iPhone users experience, therefore, people have come up with all sorts of ways to solve this problem. Here is an iPhone 6 comes with touch failure, the iPhone 6 touch function is damaged by dropping. The repair details are as follows.

professional iPhone repair tool

Firstly, replace the new iPhone display assembly.  Disassemble the iPhone 6, remove the iPhone touch screen, and then install the new iPhone display assembly. After replacement, test it,  the iPhone touch function is still not working.

Next, we need to check iPhone motherboard. Disassemble the iPhone 6 again, carefully take out the iPhone motherboard.

Use QUICK 861DW hot air rework station to remove the iPhone touch screen IC, and then re-install the touch IC. But at this time, the iPhone 6 auto reboots when white Apple appears.

Measure the iPhone motherboard via DC power supply, the iPhone boot current start from 300mA. Remove the iPhone touch screen IC , and then use digital multimeter to measure the resistance value of the iPhone motherboard, the value measured is normal.

picture 1

Remove the iPhone USB charge IC U2, and then check the boot current,  there is no change. Measure the resistance value of the U2 bottom pin,  it’s found that the F4 pin PP3.0V is shorted.

After checked the iPhone schematic diagram via ZXW Dongle, we know that this circuit is connected to iPhone big power, iPhone fingerprint power supply and U5411_RF.

Power-up again, we found U5411 – RF heating, disassemble the two components connected with U2, then the iPhone is boot, now we can confirm the U5411 is damaged., Replace the new U5411, and then test it, now the iPhone 6 can be turned on smoothly.

Finally, test the iPhone touch screen, the iPhone touch function is working properly.

 

 

iTunes Error 1: iPhone 6 Plus got an unknown error 1- Fixed!

The iPhone 6 Plus fell into water, clean up the water, after powering, there is no baseband firmware information on iPhone 6P. When use iTunes to restore it, the unknown error 1 is reported. How to fix iPhone 6 Plus iTunes error 1 problem?

The most practical & professional apple repair tools(1)

Because this iPhone 6 Plus is damaged by water, so possibly there is a problem in iPhone hardware aspect, such as iPhone motherboard. We need to disassemble the iPhone 6P to check the interior.

Remove the screws that on the bottom of the iPhone 6P, then heat iPhone by CPB screen separator, after a while, use sucker to open the iPhone screen, and then remove the iPhone display assembly.

Based on our repair experience, it this case, the iTunes error 1 possibly was caused by the problem of the iPhone baseband circuit, which including the power supply of the iPhone baseband, the communication of the iPhone baseband, and the iPhone baseband itself. Therefore, first we should measure the power supply of the iPhone baseband.

Take out the iPhone motherboard, measure the iPhone baseband power supply by digital multimeter, we found the inductor of the VERG_SMPS1_0V90 that outputted from iPhone baseband power is shorted. Check iPhone schematic diagram via WUXINJI Dongle, we know this inductor is L3201_RF.

Directly remove the inductor L3201_RF, and then measure the grounding resistance value at both ends of the inductor, we found the pin 1 of the inductor is shorted. According to the iPhone schematic diagram, we know that pin 1 of the inductor passes to iPhone baseband power .

Replace the iPhone baseband power IC by QUICK 861DW hot air rework station, and then install the L3201_RF. Measure the iPhone again, now the data measured is normal.

Use iTunes to restore the iPhone 6P, everything goes well. The problem has been fixed!

Error 53: Hardware Fix iPhone 6 unknown error 53

Received an iPhone 6 need to repair, the iPhone 6 is in restore mode state, and it prompts unknown error 53 when restore it.

professional iPhone repair tool

Trouble Phenomenon

This iPhone 6 accidentally dropped in the ground, and it causes the iPhone fingerprint failure. First we thought it’s the problem of the software, so we try to fix it by restoring. However, after we use iTunes to restore the iPhone, the iTunes reported an unknown error 53, now we suspected it is caused by iPhone fingerprint circuit failure.

Solution

Use phone opening tools to disassemble the iPhone, check iPhone fingerprint flex cable, it looks good.

Measuring the grounding data of the first pin and second pin of the iPhone fingerprint flex cable interface J2118 by digital multimeter, there is no value, which is abnormal.

Open the ZXW Dongle to check iPhone 6 schematic diagram, we know that it’s a set of I2C bus, after short connecting FL2179 and FL2195, the grounding value measured still not change, which means that possibly there is a disconnection phenomenon between iPhone fingerprint and iPhone CPU.

It’s difficult to solder a jumper wire from iPhone fingerprint flex cable to the iPhone CPU, continue to check iPhone schematic diagram, we know that this circuit is also pass to iPhone vibrator control tube U1400.

Remove the iPhone vibrator control tube U1400 by QUICK 861DW hot air rework station, and then measure the I2C solder pad of the U1400, the value is normal. Now, solder the jumper wire from B2 C1 pin of the U1400 to first pin and second pin of the J2118.

Restore the iPhone 6 by iTunes, the restore process is normal, the iPhone 6 can be turned on smoothly.

Guide: Temperature Calibration Methods For QUICK TR1300A

In order to repair iPhone PCB board or other cell phone motherboard,  we need to use a good hot air rework station, the QUICK TR1300A is the professional rework station in PCB board repairing.  However, for repairing iPhone PCB board or other motherboard, the temperature control is very important.  Here is a user guide– QUICK TR1300A temperature Calibration Method.

TR1300A

1. Power On / Off

– Power On

There is power button on the back of the TR1300A main unit, press this power button to turn on the TR1300 in hardware aspect, the TR1300A screen will lit, and then press any button to operate it. If you don’t operate it after turn on 10 seconds, the TR1300A will auto power off. At this time, you need to press and hold “POWER” button about 3 seconds to power on it.

– Power Off

Press and hold the “POWER” button about 3 seconds, or directly press the button on the back of the TR1300A main unit.

2. Temperature Calibration

Please use a good quality temperature tester; if the machine is locked by password, then the temperature can’t be calibrated, you have to enter the password first.

After changing the heating components, you need to re-calibrate the temperature, you can use temperature tester to calibrate it.

– Set a temperature value

– In the working state, when the temperature is stable, use temperature tester (such as QUICK 196) to test the temperature of the hot air gun nozzle, and write down the value.

– Press and hold the “T+” and “F+” buttons at the same time, after 10 seconds, the TR1300A will enter the temperature calibration state, the temperature value on the screen will blink,at this time, you can press “T-” or “F-” to change the value, press CH button “ENTER” to confirm the value, then calibrate successfully.

3. Setup Temperature / Airflow/ Time

Note: When you are going to setup the temperature of the TR1300A hot air rework station, please make sure the station temperature is in an adjustable state (input the right password or the password is original password “000000”). During the temperature setting process, the heater can’t disconnect the power.

– Channel Switch

There are 4 channels, they were CHO, CH1, CH2, CH3. CHO is a temporary channel, when there is no password lock, the parameters can be modified in the main interface. CH1 CH2 and CH3 are preset channels, and their parameters only can be modified in the setting interface.

Press and hold CH button for 1sec, you can switch the channel (CH1-CH3), after switched the channel, the parameter of the temporary channel CHO will be covered by the parameter of the channel you currently choose in the background. Ex: in the working state, when choose CH0, the display as the following picture.

– Increase Temperature

Press “T+” button for a once, then the temperature will up 1, if hold down the button continuously, the temperature rises quickly until the target value is reached, then release the “T+” button.

– Reduce Temperature

Press “T-” button for a once, then the temperature will down 1, if hold down the button continuously, the temperature drops quickly until the target value is reached, then release the “T-” button.

– Increase Airflow

Press “F+” button for a once, then the temperature will up 1, if hold down the button continuously, the airflow rises quickly until the target value is reached, then release the “F+” button.

– Reduce Airflow

Press “F-” button for a once, then the temperature will down 1, if hold down the button continuously, the temperature drops quickly until the target value is reached, then release the “F-” button.

– Increase Time

Press “T+”and “CH” button at the same time, then the setting time will increase 1, if hold down the both buttons continuously, the time rises quickly until the target value is reached, then release the “T+” button.

– Reduce Time

Press “T-” and “CH” button at the same time, then the setting time will reduce 1, if you hold down the both buttons continuously, the time drops quickly until the target value is reached, then release the “T-” button.

Once the working time is set, when it reaches the set time, the machine will have an alarm, after 3 seconds, you can press any buttons to cancel this alarm.

 

Fixed: iPhone 6S won’t turn on caused by Charge error

We got an iPhone 6S that comes with won’t turn on problem, the details of the failure are when charge the iPhone 6S, the iPhone 6S charging icon appears intermittently, after few time, the iPhone screen turns black, and it has no response when press the iPhone power button.

The most practical phone repair parts

According to the details of failure, we could judge that the problem is caused by charging part. There are 3 components are directly related to the charge, they were Q2300, U2300 and U4500. We can check iPhone schematic diagram via ZXW Dongle.

First step, connect the iPhone motherboard to DC power supply and test the current, the trigger current jumps directly from 200mA, while the normal current should be around 40 mA. This phenomenon is likely caused by a short circuit in the mains supply’s LDO supply.

Pic 3

PP3V0_TRISTAR, PP3V3_ACC this two are supplied by all LDO power supply, so the most likely damage is the USB U4500 IC. Remove the USB IC with QUICK 861DW Hot Rework Station , trigger current about 40mA, and then replace the USB IC.

After replacing the iPhone USB charge IC, turn on iPhone and test it, the iPhone 6S is turned on successfully, after entering the IOS system, test the iPhone charge function, it works properly.

iTunes Error 56: Fix iPhone X has 56 error and won’t turn on

Why the iPhone X won’t turn on, and it reports unknown error 56 when using iTunes to restore it?  Now, we need to find out the reason and then fix it.

After learning more about the details, we know that this iPhone X had dropped into the ground, after picked it up, it can’t turn on anymore. Connect it the computer, and then use iTunes to restore it, it failed and reported unknown error 56.

As we know, the iPhone X  motherboard has double layer, and  the two motherboard  layer of the iPhone X is connected by a middle column, so the pins are easy to drop.

Because the iPhone X had dropped before, so it may be the pins that the iPhone NFC chip to iPhone CPU part are drop off.

Disassemble the iPhone X, take off the iPhone motherboard, use QUICK 861DW hot air rework station to separate the iPhone motherboard, and then we see that there’s a row of pins had dropped off.

Pic 2

Open the ZXW Dongle to check the iPhone X bitmap, we found the circle around it is all the grounding wire, and only dropped 6 pieces useful pins. The grounding wire doesn’t need to be filled, we just need to fill these 6 pieces useful pins, these all are the signal line of the NFC chip, so the iPhone X will report unknown error 56 when it is restored.

Pic 3

Next solder the tin on the middle column, and then weld the AP part back to the iPhone motherboard.

Pic 4

Assemble the iPhone X, now the restore process is finished properly, the iPhone functions tested are normal, the repairs are end here!

Summary:

This fault is caused by the dropped pins from the signal of the NFC chip through the middle column to the CPU, and then it causes iPhone X error 56.

iTunes Error 9: Fix iPhone 7 Plus error 9 and won’t turn on problems

An iPhone 7 Plus won’t turn on and has iTunes unknown error 9 problems, what’s trouble? How to fix? This iPhone 7P has been damaged by water,  but it still can be used, after a day, the iPhone 7P won’t turn on, it always restarts automatically, and the iTunes reports unknown error 9.

professional iPhone repair tool

Disassemble the iPhone 7P by phone opening tools, and then take out the iPhone motherboard.

Based on our repair process, for the error 9 on the iPhone 6S and later iPhone, mostly it’s caused by the problem of the iPhone Nand flash and iPhone logic eeprom IC.

First, measuring the power supply of the iPhone Nand flash by digital multimeter, the 3V, 1.8V and 0.9V all are normal.

Now we need to check the iPhone motherboard, directly use QUICK 861DW hot air rework station to remove the iPhone Nand flash, and replace it with the new one, after replacement, it still reports unknown error 9, then perhaps it’s the problem the iPhone eeprom IC. Directly replace the iPhone eeprom IC, after replacement, it still reports error 9.

The iPhone Nand flash and iPhone eeprom IC all is fine, so, what’s wrong for this iPhone?  Check iPhone 7P schematic diagram via ZXW Dongle, we can see that there are 2 resistors next to the iPhone eeprom IC.

As we know, if the resistance deviation of the two resistors next to the iPhone eeprom IC is too large, then it will cause an error, so try to fix it by replacing these 2 resistors. Put iPhone motherboard under the Trinocular Integrated Microscope, remove the logic eeprom IC and the resistors connected it, and then replace them with the new one.

Pic 2

After replacement, connect iPhone 7P to the computer, and then use iTunes to re-brush the iPhone again, the brush process bar is running properly and successfully,  there is no unknown error code.

Install the iPhone 7 Plus and test it, the iPhone 7 Plus can be turned on smoothly. After entering the iOS, all functions tested are normal.

 

Solved: iPhone 7 No Service After Nand flash Expanding

Received an iPhone 7, the fault described by the customer is that the iPhone 7 has no service, and this iPhone 7 memory has been expanded to 128GB in other place, after expanding the iPhone Nand flash, the iPhone 7 always shows no service, searching, and final white Apple restart. After brush iPhone to IOS 12, it can enter the system, but still no service and it can’t be activated.

phone repair Tools& equipment-2

Disassemble the iPhone, use digital multimeter to measure the power supply capacitors around the iPhone baseband power IC, we found the PP_1V0_SMPS5 is shorted. Generally, this case is caused by a short circuit of the iPhone baseband. Remove the iPhone baseband power, and then measure the PP_1VO_SMPS5 again, it’s still shorted.

Pic 1

This is a designed flaw of iPhone 7 Qualcomm version, the iPhone baseband S5 power grounding connect point seems to be disconnected, but not, and it cause iPhone baseband burned.

Pic 2

The solution is put iPhone motherboard under the Trinocular Integrated Microscope, re-connect the S5 grounding connect point, and re-install the iPhone baseband power, borrow a PP1V8_SDRAM on the C3211, pass through a 2.2K resistor to C5701_RF, and then forcibly pull up PP_1V0_SMPS5.

Pic 3

Finally, install the iPhone 7 and test it, now the iPhone signal is normal, the iPhone is working properly.

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