Repair iPhone 6 Cannot Boot while Charging

Got the iphone, attached file described：iPhone 6 can't boot while charging .

Tested by multimeter, the current shows 80mA. So we decided to remove the  iPhone 6 motherboard while taking the USB off, but the current kept the same. We measured the I2C resistance  which shows the fault sources, as shows in picture11-10-1.

Since it's short circuit, it means the connected chip is damaged, the connected chips have display, backlight, main power supply USB and the iPhone 6 CPU. 

First observe with microscope, it is found that all the backlight diodes are burning and dis-coloring.

Then remove the backlight first, it does not short-circuit. The trigger current is normal, so continue to replace the 3 piece of iPhone backlight chips.

According to our past experience, if the large inductors gets discoloring, the large inductors with connected backlight would also have problems, so we replace them together. As shown in picture 11-10-2.

After the replacement, the current is triggered normally, Install the USB to turn on the iPhone 6, the functions are all tested normally. As shown in picture 11-10-3.

Detail process to handle iPhone 6P LCD no display CPU issue

Aim to fix every repaired phone.

The customer delivered his iphone 6p to us, Attached the file describes:  LCD Screen has no display and no light while booting. We checked it after we disassembly it , then we found the motherboard was repaired before. We have to take 4 steps to fix it. Following the steps:

1. Measure the working condition of iPhone LCD display IC, all is normal. Then measure the display socket J2019 with Fluke 15B+ Digital Multimeter, we found the #3 pin is short circuit. 90_AP_TO_LCM_MIPI_DATA3_N MIPI image transfer data bus leads directly to CPU, the initial diagnosis is that the CPU is continuous tin or internal damage. As shown in Picture 11-9-1

2. Remove iPhone CPU and then measure this signal line, we found it is the earthing short circuit, which is CPU internal damage, the kit is damaged. 6P and 6 are not the same size; the circuit design is also not the same. By analyzing the WUXINJI schematic diagram, we found the solution.As shown in Picture 11-9-2 and picture 11-9-3

 

3. According to the comparison of WUXINJI schematic diagram, we found that iPhone 6 Plus has one more a set of MIPI image transfer data bus than iPhone 6, 90_AP_TO_LCM_MIPI_DATA3_P、90_AP_TO_LCM_MIPI_DATA3_N, and iPhone 6 doesn't have that line. Because the iPhone 6 only needs to display 4.7 inch images, but iPhone 6 Plus needs to display 5.5 inch images.

4. The faulty iPhone 6 Plus is 90_AP_TO_LCM_MIPI_DATA3_N short circuit, we decided to abandon the 5.5 and install the 4.7 directly. Move the CPU on this fault board to iPhone 6 motherboard, the iPhone LCD can display now！

Repair iPhone 6 200mA electric leakage

It is a serious phenomenon for current leakage. 

The next iPhone 6 we will repair is in a bad situation.

We should tear down the battery before we start to test it. Connecting it with multimeter, the current value shows 200mA,so we directly change an USB tube. Then we do it again ,but the same result.

So we wonder if there is another fault symptom happened, the last repair technician mentioned the iPhone 6 fingerprint is not good.

When heard of this problem, we can basically judge where the problem is. Connecting multimeter and trigger the on-off current with 300-400 mA, this is not normal. There must be something wrong with the fingerprint 3V. Use the multimeter to test fingerprint 3V against the ground value, it is short. This kind of situation is generally caused by one of outside capacitance is short, dismantling it! Finally, we find out the C2133 is short circuit, pry it off with phone IC repair knife, reboot the iPhone 6 and retest the standby value is normal, and the fingerprint is also normal now.

The iPhone 6 schematic diagramIC postion is shown in picture 11-8-1.

Summary of leakage detection process:

We must test the function of system as possible we can in advance if we encounter the leakage, which will be repaired if any of the functions are tested abnormal.

If all is normal, USB tube will be required to pay more attention. USB tube is also a problem, if it gets bad, the function will be normal and no problem can not be detected;

If there is a electric leakage on the iPhone, you can first press the iPhone power button and loose to see how much the current will be. In the normal case, it is about one hundred; 

If it jumps to three hundred or four hundred, there must be electric leakage, and jump to two hundred or three hundred leakage is basically caused by several 3V: The 3v power supply of USB tube, the 3V of fingerprint and the 3V of compass.

Have iPhone 6P screen half dark even no display issues solved

Fault Description: iPhone 6P  touch screen half dark while it can receive call while it will become no display once in a while.

As we only received an iPhone motherboard. so the first step we took is to check it with multimeter, the result shows it was repaired ever while iphone backlight also was replaced. And one of the capacitor was lost, we should treat it seriously.

Following the solve way and detail pictures:

                                                                                           Picture 11-6-1

Now we directly remove the yellow insulation tape, cleaning up the repaired place, and then supply power on it to test, the left backlight is dark.

                                                                                            Picture 11-6-2

After using the QUICK 861DW to weld the capacitor that didn't install before, turn it on and test it, now the backlight is back to normal, it can display normally. According to check the WUXINJI circuit diagram, we know that the backlight is a step-up capacitor, if none of this; it can't boost the voltage, so the backlight is not bright.

                                                                                          Picture 11-6-3

                                                                                         Picture 11-6-4

After fixing the backlight, we also need to repair the screen sometimes display but sometimes doesn't display issue. Sometimes it can display when you press the socket with your hand, so we thought it was a problem with the socket. However, after careful examination, we found that the socket has been replaced, and the pin also is fine, now we have to check its circuit.

After testing, we found that there is no display power supply -5.7V. As we know, -5.7V is directly output by the iPhone screen display , testing the line, it is normal. So we decided to replace the display IC directly. After the replacement, turn on the iPhone, now the iPhone screen works normally!

Different way to fix iPhone 6 Plus Touch Failure

We should treat every sick phone carefully, especially it takes the important data. As the scene we saw, iPhone 6P touch can't response after we pressed it  while the customers said there has some important data. So we have to check it carefully, let us take some effective measures to fix it:

1. The failure is that the touch can not be used, we still follow the rule: easy operation first, first replace the iPhone screen, the touch is still no working.

2. After excluding the screen problem, we judge it's iPhone motherboard problem.

3. Remove the motherboard and connect to measure touch voltage, PP5V7_SAGE_AVDDH touch +5.7V is normal, PP5V7_SAGE_AVDDH touch the -5.7V voltage has no value. As shown in 11-5-1.

4. The other points are found to be normal, power off to test whole circuit, we find circuit line is broken. Picture 11-5-2

5. Soldering the broken line with jumper, connect the 2 points in iPhone diagram with jumper wire as shown in picture 11-5-3, actual picture as shown in picture 11-5-4.

6. Connect screen to measure the iPhone screen control IC U2402 (sub touch chip boost work).As shown in picture 11-5-5.

7. Install to test, the iPhone 6 Plus touch can work in a normal way now, repair ends here!

Detail Process To Fix iPhone 6P Speaker No Sound Fault

No sound while you receive a call or play music, maybe you should take some cost to fix it, but it is a easy problem,

Let me show you the ready work firstly,

 1. Check the current and voltage between the iPhone tail plug and audio

2. Replace the iPhone audio IC

3. Check the line from audio to iPhone CPU to see if it is normal

Repair Process

1. Use JM-9102 Disassemble Tools to replace the iPhone rear shell assembly, and then test it, the fault still exists.

2. Use Fluke 15B+ multimeter to measure the resistance value from tail plug socket to small audio, all is normal.

3. Remove the small audio and then measure the line from small audio to iPhone A8 CPU. After measuring the diode data of SPKAMP_RESET_L, we found its data showed infinity, it may be caused by the disconnection or CPU virtual welding. In this step, WUXINJI schematic diagram will help you a lot.

                                                                                       Picture 11-3-1

                                                                                       Picture 11-3-2

4. After communicating with the customer and stating the risk, we can start to pry the iPhone CPU by S1018 CPU remove tool and use QUICK 861DW rework station to solder the jump wire.

                                                                                      Picture 11-3-3

                                                                                    Picture 11-3-4

After finish the above step, assemble the iPhone 6 Plus, turn it on and test it, now the caller ringing is back to normal, this iPhone 6 Plus has been repaired!

How to save an iPhone7 after Dropping??

We got a dropped iPhone 7, it sounds terrible right for its master, right? And the customer describes his iPhone was dropped without iCloud, of course, it can’t boot. So the next thing we should do is to fix it, and then change it to the iPhone which with iCloud lock. After a whole checking, the iphone was hurt seriously because of the dropping. The screws on motherboard have been dumped, as shown in picture 6-3-1. 

Firstly, Connect it to UD 1505TA DC Power Supply , the result shows large current leakage; Secondly, we start to measure, we found the iPhone NAND Flash 3V power supply was short circuit. After a totally observation, we found the iPhone motherboard slot position is bent, we doubt it may be the reason to cause the short circuit. Then we remove the two capacitors which on the side of the NAND flash, detecting it again with Power supply, the value turns on normally ,Picture 6-3-2.

Turn on iPhone and test functions on iPhone, we found there is no WIFI; sometimes it will be stuck when into the settings. After measuring with Fluke 15B+ Digital Multimeter, the side of wife clock signal r0807 has 1.8V, the other side which is through to wifi module 17 pin has no voltage. Replace the resistance, and weld the jump wire by QUICK 861DW rework station, the fault is still exist. Decisively remove Wi-Fi module, and then the solder pad drops points, it is common in the iPhone that dropped, weld the jump wire first, as shown in picture 6-3-3.

The WIFI module also drop points, we can check it under the 7-45X Trinocular stereo microscope. We want to test functions by turn on iPhone without installing Wi-Fi module, but when apply power on it, it's leaking again. Now, we need to use the rosin methods to fix it.  After remove the heating capacitor, power on iPhone and test it, the setting function is normal now. Next we need to install WiFi module, after finish it, test the function, the Wi-Fi is back to normal. However, sometimes it restarts automatically,Picture 6-3-4.

Considering there is a slight distortion in the middle of the iPhone motherboard, the audio can cause a reboot, so we remove the audio first, also drops points. After soldering jump wire, turn on iPhone and test it, all functions is normal now.

Now we need to replace external configuration. Use JM-P01 Essential Electronics Toolkit to disassemble the iPhone that with iCloud lock, please be careful not to break the line of the iPhone. Then replace the fingerprint that on the iPhone screen, because the under of fingerprint have glue, so please be careful not to damage the IC,Picture 6-3-5.

Finally, install the repaired motherboard, assemble the iPhone, turn it on and test it, now all is normal. The iPhone 7 has been repaired!Picture 6-3-6

Fast & effective fix the iPhone 6 can't natural boot

People are undoubtedly pleased upon getting their Apple phone that is the highest-tiered smartphones like the iPhone 6 or iPhone 6, iPhone 7, iPhone 7 Plus, etc. But a few months later, many owners were vexed when devices issues began to emerge. Maybe you went through these process that is iOS 11/10.3.2/10 update, screen replacement, restore from backup, update iOS to previous version, etc. But the iPhone cannot boot again, you don't know the reason and it is the software or hardware problems. Now Vip Fix Shop Team will show you the fix process that is iPhone 6 cannot boot under the retain data situation.

Phone fault: The iPhone 6 doesn't boot, the boot current is 700mA. Picture 1-1

Fix process:

Disassemble the iPhone by phone opening tool, take out the iPhone motherboard. Connect it to DC power supply, the boot current shows 700mA, which means there is a power supply short circuit. Picture 1-2

Open the phone circuit diagram and check it, we can find that the diode data of PP1V8_SDRAM is low. Picture 1-3

Measure the diode data the PP1V8_SDRAM with multimeter, the data only have around 100, it is lower than normal data. Picture 1-4

According to the repair experience, this group abnormal power supply was caused by damaged capacitor at lower right corner of iPhone CPU. As shown in picture 1-5. We just pick it off.

After remove it, measure the diode data again, now the data is back to normal. As shown in picture 1-6.

Finally, assemble the iPhone and test it, now it can be successfully powered on and smoothly into the IOS system. Picture 1-7.

Get the lost ID for 4G Version iPad Air2

The only way to unlock ID is change the 4G version into Wi-Fi version. Of course, the adopt way is easy to operation. As long as we adhere the right way to fill the iPad R0505 resistor on the GPIO_ID signal in a suitable environment.

Following the R0505 resistor-iPad schematic diagrams:

                     Picture 10-14-1

                     Picture 10-14-2

Flash WiFi version firmware, if it's processing normally, WiFi will not be used. There are WiFi address on the iPad but we can not open, it will become gray when opening the WiFi sign.

                     Picture 10-14-3

                     Picture 10-14-4

In front of this kind of situation, we need to replaced a iPad WiFi Chip called 339S0251, so that it can be used normally.

During the repair process, the tools we have to use are solder station, tweezers, solder flux, etc.

Finishing the above replacement of Wi-Fi,installing to test the ipad device. It can work again, ID unlock repairs are ended.

Solve the Dead iPhone A8 Processor

Because it is a water damaged phone, so we doubt whether it has caused short circuit. Connected with 80ma, measuring result is 0.8v;Removing the  iPhone USB management IC (U1700), iPhone display touch IC (U1501) and replacing PMU, the result is same, as the resistance value;We can judged it is not short circuit. Then we removed the CPU, the reset value is normal 1.8 which lower again after installing reset voltage.

Fine, We can judge it is caused by  iPhone CPU. The reset pull-up resistance R0206 is 100K while the voltage becomes 1.6 after the change of the 2.2k resistance.

The upper cover current is a little higher, and the iPhone screen is not displayed when install to test the iPhone 6 device. The power supply required for the measurement screen is normal, connect Ace assistant which shows "please unlock the device", so it indicates that the system has been entered, and the failure is from CPU. Then PP1V0 is measured short circuit, a few points  on CPU are all short circuited. Now, we have to install the CPU back.

                                     

Directly connect 1.0V to this point, the current is 350A and the voltage is 0.8V. It seems hopeful, so we connect it with PP1V2_SDRAM directly.

After we finished the above operation, we can see the iPhone6 turns on a bright screen. Though the current is about 400mA, the data is kept.

The way to handle iPhone6 Plus Front Camera Can’t Work

After we reboot this iPhone got from my friends, all of the functions showed normal, switched normally between front and camera. But the iPhone front camera is shown full black screen when taking photos. As shown in picture 9-10-1

First, we need to judge where the problem comes from. This failure is generally caused by data hub, because the problem came up after falling, so it is likely to be caused by the disconnection or iPhone CPU false welding.

Disassemble and install a new camera, same fault phenomenon remains the same, the problem is determined on the iPhone6 Plus motherboard.

Power off the phone and measure the ground value of the camera interface, there is no any problems has been found, also the voltage needed for the camera is measured normally. This is a rare situation. If the CPU is false welding, the resistance shouldn't be normal, so there is almost impossible for getting a bad CPU.

Test the interface resistance again, infinity is detected when the 19th pin AP_BI_FCAM_SDA_FONN is measured. As shown in picture 9-10-2.

Many tests found that sometimes it's infinite, sometimes more than 500 of the resistance, but according to the data cable comparison found that under normal circumstances, it should not exceed 500. Measured value on multimeter is as shown in picture 9-10-3.

Tracing the source, it was found that the AP_NO_FCA_SDA_CONN was connected to the CPU by inductance, and the resistance of the 1 pin measured by FL1114 was normal. As shown in picture 9-10-4.

After measuring FL1114's 2 pin infinity, we find that some inductance is loose, after sodering, 19 pin resistance become normal.

Booting and entering into the system to test, the front camera has been fixed already!