博文

目前显示的是 十一月, 2018的博文

Repair Guide: iPhone X shows error 4013 after water damage

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We received an iPhone X. The customer said that after the iPhone X fell into the water, the iPhone was in recovery mode and reported a 4013 error on recovery. How can I fix this failure? According to the customer's description, the iPhone fell into the water, but did not drop the line. In this case, we can eliminate the baseband problem. After receiving the iPhone X, we first restored the iPhone through iTunes, and iTunes reported an unknown error 4013, which is the same as the iPhone baseband issue. Exit the recovery mode, remove the iPhone, and connect it to a DC power supply to check the iPhone current. When the iPhone screen is not connected, the iPhone X can enter the IOS system. When the front receiver flexible cable is not connected, the iPhone can be opened smoothly. Observe the iPhone display screen under the Stereo Zoom Microscope , we found the iPhone receiver has the trace of the water. Remove the front receiver sensor flex cable, we found the photosensit

How to repair iPhone 7 home button return function

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We got a faulty iPhone 7 from the customer. The fault description is that the iPhone's home button has no return function.  Nothing happens when the home button is pressed.  How can I fix this fault? First, go to Settings > Touch ID and Password, "Add fingerprint to gray. We judged that the iPhone 7 home button is completely damaged. Is the home button function not working due to the faulty home button fingerprint flexible cable? In order to fix the home button, we need to disassemble the iPhone with phone opening tool . First of all, remove the display assembly and take out the logic board with QUICK 861DW Hot Air Rework Station, then remove the vibrator, speaker and charging port flexible cable, replace the new one. Next, install the vibrator and speaker. The second part is a custom Home Button Flex cable. Fold it in half and install it. Then get the iPhone logic board and install it there. The last part of our customized return-to-home group is the home but

iPhone 6 Plus Screen No Display,Here is repair !

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We received an iPhone 6 Plus from our customer, the faulty described is that this iPhone 6 Plus screen doesn't display, after replacing the iPhone display power IC, the problem is still exist, and they don't know how to fix, so they send iPhone 6 Plus to us. The following is the repair steps. First of all, disassemble the iPhone 6P with the  phone opening tools, carefully take out the iPhone motherboard. Put iPhone motherboard under the Stereo Zoom Microscope and then use QUICK TS1200A hot air gun to re-weld the iPhone display power IC that has been replaced by co-worker, and then test it, but the iPhone screen is still not display. Now use digital multimeter to measure the power output voltage -5.7V and 5.7V of the iPhone display IC, there is no output, which means the iPhone display power IC doesn't work properly. Check U1501 working principle with the WUXINJI Dongle, we know that if the iPhone display power need works properly, it must have 3 conditions, th

iPhone 7 can't boot,cpu repair steps!

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A week ago, the customer sent us an iPhone 7 that could not be turned on. After we received the device, we detected a short circuit on the iPhone 7 CPU. The following are the steps to repair it. First use the iPhone open tool to remove the iPhone and disconnect the battery, then connect the phone to the DC power supply , the current reading of the ammeter jumps to 350 mA and then remains still, which is an abnormality, indicating that the logic board is shorted. Disconnect power and remove the logic board. Measure the capacitors around the power IC one by one. Except C1823 all values are normal - 0 is displayed, which indicate a short circuit in C1823. Observe schematic with WUXINJI dongle(VC696) , C1823 is the filter capacitor of PP1V8-SDRAM, which is directly connected to the CPU SDRAM. Connect the logic board to the PCB bracket, use QUICK 861DW hot air rework station to heat shield cover , and then remove the CPU SDRAM with a CNC chip grinder. After grind the chip, at

How to repair iPhone 6S receiver without sound when making a call

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We received an iPhone 6S, and the customer reported that the receiver had no sound during the call and he could not hear the other side. He suspects that the iPhone speaker is broken. The client wants us to fix it. When we turn on the speakers on the iPhone, we can't hear each other. According to our maintenance experience, the iPhone receiver has no sound, but the iPhone speaker can hear the sound. This problem is usually caused by the iPhone receiver, receiver flexible cable, receiver circuit or iPhone audio IC . First we need to test the iPhone 6S. Turn on the iPhone 6S, go to Settings -> Sound and Touch to test the ringtone, and the tested ringtone is normal. Call someone else, the receiver has no sound, but the speakers are normal. Now, replace the receiver and flex cable, and then test the iPhone 6S, but the failure still exist. Use digital multimeter to measure the diode data of receiver signal 1 pin and 3 pin that on the connector J3100, the data measured are

iPhone 7 Plus half-dark screen, how to fix it?

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We received an iPhone 7 plus, and the customer said that the screen backlight problem, including no backlight, dim backlight, half backlight, or the screen can not be opened. Here, we will introduce the iPhone 7 Plus half-backlight repair case and related backlight circuit repair caused by the pseudo soldering of the display connector. For mobile logic board repair, inspection is always the first step. Place the logic board under a trinocular stereo microscope and double check that there are no signs of water damage and deformation. Next, let's assemble the iPhone and test it. Install the logic board and display components. Connect to the DC power supply and press the power button, the screen lights up and the Apple logo is displayed. We can see that the right side of the screen is darker than the left side. Thus, it is judged that the failure may be related to the backlight circuit. Use phone open tools to unpack the iPhone and remove the display assembly. Take out the

How to repair iPhone 6S Plus weak WIFI signal problem

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The customer sent us an iPhone 6S Plus. He said that the iPhone 6SP WIFI signal became very weak after the line was dropped, and the WiFi network speed was very slow. After receiving the iPhone, first test WIFI on the iPhone 6S Plus, the WIFI signal is really weak. When connecting to WIFI, "Cannot join this network" is displayed. The iPhone weak WIFI signal problem for this dropped cable is mostly caused by the faulty iPhone WIFI IC . Use phone opening tools to disassemble the iPhone 6S Plus, take out the iPhone motherboard. Attach iPhone motherboard to the PCB holder fixture, and then put it under the Stereo Zoom Microscope . Use QUICK 861DW hot air rework station to heat the iPhone WIFI IC, and then use tweezers to remove the iPhone WIFI IC, we found there are many pin are missing, and most of them are useful pins. Because replace iPhone 6S WIFI need to unbound the WIFI on the iPhone Nand flash , otherwise, the iPhone WIFI function can't be used. Now, remo

My iPhone 7 iTunes has error 4013, how can I fix it?

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The customer sent us an iPhone 7 and his iPhone 7 fell into iTunes Error 4013. Before repairing, press the power button to turn on the iPhone. The phone card is in iTunes recovery mode and cannot access the system. Connect it to your computer and recover via iTunes, error 4013 occurs during the recovery process. How to fix this phenomenon? iTunes Error 4013 of iPhone 7 usually caused by pseudo soldering or damaged CPU. The error may be related to the power supply of the baseband PMU or NAND flash. Since CPU repair is very difficult, so we can check the power of the baseband PMU and NAND flash at first. Connect the iPhone to the DPS DC power and measure the voltage of the baseband PMU C5623 and C5631. The result shows that the values of C5623 and C5631 are normal. So we judged that the power supply of the baseband PMU is normal too. Fault Repair Let's pay attention to the NAND flash power supply, remove the black adhesive around the NAND flash with QUICK 861DW Hot

Repair Guide: iPhone 6S can't open after dropped into the water

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Recently, some users have reported that they accidentally dropped their iPhone into the water and could not boot after picking up. They don't know how to fix it. Today we will be launching a repair tutorial on how to fix the iPhone 6 after dropping into the water. Remove the iPhone 6S by phone opening  tool and connect the iPhone motherboard to the DPS DC power supply , which leaks 120mA. After the trigger, the current is stuck at 360mA. Remove the iPhone motherboard and observe it with a microscope. We found that the iPhone baseband power IC, NFC IC, iPhone Big Audio IC and iPhone monitor power IC have water traces. Clean up the iPhone motherboard with iPhone PCB cleaner, and then connect it to the DC power supply again to observe the current, now the current turns to 80mA, after triggering, the current is stuck in 300mA. At the same time, we found the iPhone display power IC was repaired before, and the corner of iPhone display power IC was damaged. Remove the iPhone

My iPhone 7 Plus can't be started, how can I fix it?

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The customer sent us an iPhone 7 Plus. His iPhone can't boot, he tried it many times. And his iPhone NAND flash is broken. He didn't know if he could fix it. So he needs us to help. After receiving the iPhone 7 Plus, first, we tried to replace the new iPhone NAND flash . Then reinstall the iPhone, brush it and test it. The result is shown in the figure, showing iTunes error 9 after displaying the Apple logo. It is worth noting that this type of problem may be caused by NAND flash causing CPU disconnection or CPU virtual soldering. Now we have ruled out NAND flash. Before installing NAND flash, test the resistance of the NAND flash using a digital multimeter . The results show that the seat is no problem, so the CPU is the key. Remove the CPU and reinstall it! Then brush the machine again, now the black apple logo has recover normal. But don't happy, brushed the machine to the bottom of the Apple logo, iphone reported error 56. Reanalyze the problem, iPhone

How to repair iPhone 6 fast power consumption and overheating problems?

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The customer said that his iPhone 6 would overheat and consume quickly during charging and use. He didn't know what caused the failure. He wants us to fix it. Below are our repair steps. First, test the iPhone 6. After using the iPhone 6 for a while, it became very hot and the iPhone battery was very fast. Second, disassemble the iPhone. Use the phone to open the tool to disassemble the iPhone, connect the iPhone to the DC power supply , the iPhone can be turned on, and it will enter the IOS system smoothly. When the iPhone display is off, test it and we find that the working current is stuck at around 250mA, which is not normal. Continue to test the each functions on iPhone, we found the compass can't be used. Take out the iPhone motherboard, use digital multimeter to measure the diode data of the compass IC power supply. After measuring, we found that PP3V0_IMU this voltage is short-circuited. Check iPhone 6 schematic diagram via WUXINJI Dongle , we know that the

iPhone 6S shows error 21, what should we do?

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The customer sent us an iPhone 6S. He said that the iPhone 6S showed error 21, although the customer replaced the NAND flash, but the machine still does not work during the test. How can I solve it? To get the iiPhone, first connect to the DPS power to power up, and set the current to 60mA, DFU current, plug in the computer to go online, and then brush, as described by the customer, the screen displays error 21 when the screen is open. After reporting an error, the screen stays lit. After replacing the external device, the brush failure still exists. The QUICK 861DW hot air rework station was used to remove the main board and observed with a stereo zoom microscope . We found no suspicious points. Test CPU and NAND flash power, all of which have power. Since NAND flash has been moved before, it starts with NAND flash. Disassemble the NAND flash, test resistance of pin with digital multimeter , the resistance is normal, replace a iphone NAND flash and brush machine again,

My iPhone 6S can't boot after dropping on the ground, what should I do?

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Have you experienced accidental dropping of your phone? Our customer encountered this situation with his iPhone 6S. Unfortunately, the iPhone6S that fell behind could not be activated, and did not respond when the iPhone power button was pressed. How can we fix it? First, use the iPhone Opener to carefully remove the iPhone 6S, remove the iPhone display component, disconnect the iPhone battery, and then remove the iPhone motherboard. Use digital multimeter to measure the diode data of main power supply for each circuit on the iPhone motherboard, we found the diode data of PP_CPU voltage is smaller than normal value. Because there are many components are connected to the PP_CPU, so we are going to use rosin method to find out the short circuit part.  Put iPhone under the Stereo Zoom Microscope , apply rosin to the soldering iron tip, and them smoke the rosin evenly on the surface of each component. Short connect boot pin to turn on the iPhone, we found the rosin of the C20

Repair steps: iPhone 7P can't turn on

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We received an iPhone 7P from the customer, and the fault description is that the phone cannot be turned on. How to fix? Please read below. First, plug in the iphone power cable to measure the charging current. The input current is about 200 mA and still jumps. Connect to your computer and it won't open. Next, remove the machine and connect the DC power supply and we found no current. There is no leakage on the front side, triggering a large current, reaching 1.9A. Then, it is easy to spray the rosin onto the power supply and the current appears. When we saw this, we all feel frustrated. Does the main power supply has failed? We decide to open the circuit diagram. And open the hot spot, we find there is the NAND flash power supply. Test whether there is a short circuit in the NAND flash! Without surprise, the fault from here after testing with digital multimeter. Because the 6s machine has many problems, what can we refered to is NAND flash at first. Click a few points

How to repair iPhone 7 Plus will not charge and no sound

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We received an iPhone 7Plus, the iPhone 7Plus malfunction is very strange, the customer said it can not be charged and there is no sound. After communicating with the customer, he accidentally dropped the iPhone 7 Plus to the ground, and then the iPhone camera would not take a picture. The iPhone had no sound and the iPhone was not charging. After receiving the iPhone, it has a lot of problems, but we need to fix it one by one. First we need to solve the iPhone charging problem. Plug in the iPhone lightning protection cable, we confirmed that the iPhone 7P is not charging. Connect the iPhone 7P to your computer and the computer will not recognize the device. Now, we confirm that the iPhone 7P charging problem is caused by the iPhone USB charging IC . Remove the USB charge IC from the iPhone motherboard, use digital multimeter to measure the grounding resistance value of the solder point on the solder pad, we found the resistance value of the C3 is infinitely large, and this s

iPhone X can't be charged, how to repair it?

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The customer sent us an iPhone X that could not be charged. How can we fix it? Below are the detailed repair steps provided by our phonefix shop team. After getting the motherboard, considering the charging failure, we first use the WUXINJI dongle to check the schematic on the iPhone X. Insert the iphone tail plug cable and connect it to the 47, 48 pins of the J6400. The 5V input voltage is PP-VBUS1-E75, and the 20-pin HYDRA-CON-DETECT-CONN-L will be pulled low. U3300 output PP--VBUS1-E75-RVP and sent to U6300 via R3360 again. HYDRA-CON-DETECT-CONN-L changed the name to HYDRA-CON-DETECT-L via R6410. HYDRA-CON-DETECT-L send the G3 pin to multi-function electronic switch U6300. When the U6300 receives a low level signal is also used to identify the link of iphone charging cable . U6300 receives 5V power supply, and being tested that when tail plug being accessed, it will feeds the information back to the CPU through the UART data interface. After receiving the 5V, th

iPhone X can't boot, this is the repair step!

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A customer sent us an iPhone X for repair. The fault described was that the iPhone did not turn on after it fell, and reported an error 56 after recovery. How to repair it? Please read this article! The iPhone X is connected by two motherboards through the middle column, so the pins are easily lost. Now, it may be that the pin from the NFC chip to the iPhone CPU is dropped. Check the iPhone schematic by WUXINJI Dongle , which is surrounded by the ground and 6 useful pins are dropped. The ground lines are no need to fill, we just need to fill these 6 useful pins, we can check it under the Stereo Zoom Microscope . These all are the signal line of the NFC chip, so when we restore iPhone by iTunes, it reports unknown error 56. Next we need to plant the tin in the middle column, and then re-weld the AP part. Install the iPhone motherboard, assemble the iPhone, and then re-flash it again, now it flashes smoothly, all functions tested are normal, the repairs end! T

How to fix iPhone 6S can not start after fell into the pool

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iPhone can't open, what should I do? Recently we received an iPhone 6S, the customer described his iPhone accidentally fell into the pool and could not be opened. Before that, he went to the repair shop for repairs, but it was not repaired. He needs our help. First, dissemble iphone with iphone opening tool , we saw that the motherboard was flooded with water, we cleaned the water area thoroughly, it seems that CPU Upper also exist fault. After tested resistance and powered on, there is no short circuit. Connect the iphone motherboard to the DC power supply, we find the current value is about 240MA. Test PP-VCC-MIAN with a digital multimeter , exist phenomenon of short circuit, the resistance is small, only dozens of ohms. Observe carefully, we found that capacitor next to the WIFI chip was black seriously. Use QUICK 861DW Hot Air Station to remove the capacitor,  resistance is tested more than 100 ohms, and the current measured is also more than 100 mA. Due to the lar

How can I fix the iPad 5 failing to boot?

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We received an iPad 5 and described the failure that the iPad 5 could not be turned on. First connect the iPad to the DC power supply trigger it to test the current, and the current is stuck at around 40mA. Connect the iPad to the computer and restore the DFU, it reports an error 40. After entering the recovery mode, we found that the SN was not recognized. Based on the error code, we judged this to be a circuit problem with the iPad Nand flash or iPad Nand flash. Remove the iPad 5 and take out the iPad motherboard. We found that the iPad Nand flash has traces of disassembly. Measure the 1.8 and 3.3V of the iPad Nand flash, both without power. Check iPad schematic diagram via WUXINJI Dongle , we can know that power supply for both sets of circuits is converted from U3850. Because the iPad Nand flash was disassembled, so we suspected that the power supply tube was virtual welding. Re-install it, the power supply is back to normal, but the iPad still won't turn on. Now

iPhone 7 Wifi and compass troubleshooting

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The customer sent us an iPhone 7. The fault description is WIFI, Bluetooth cannot be opened, and there is a leak. After testing, we found that Wiif could not be opened, but Bluetooth could be turned on and the compass had problems. Set the backlight to be the brightest and the screen to be dark. Based on past repair experience, we believe that damage to general functional modules can lead to leakage and rapid power consumption. Since the Wifi function could not be activated, it may be caused by damage to the iPhone Wifi IC . First, disassemble the iPhone,  use DC Power supply  to power on, indicates that the current is missing, trigger more than 100 jumps. Then open the motherboard with QUICK 861DW Hot Air Rework Station we discover it is a water machine, but before that, the customer didn't tell us. Observe the iPhone under stereo zoom microscope and see that there is corrosion next to the Wifi. Maybe this is where the fault lies. Clean corroded area with wa

How to solve the iPhone 6 gray WiFi failure

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The customer sent us an iPhone 6 for repair. The fault described is that the iPhone WIFI cannot be turned on and the display is gray. Have you ever encountered this situation? This is a very crashing thing. Today we will teach you how to solve this problem. After we received the iPhone 6, we tested the iPhone WIFI, it really didn't work, we needed to disassemble it and fix it. For this problem, first we can directly replace the iPhone WIFI IC . After installing the iPhone WIFI IC, the iPhone 6 was turned on, but it stuck when entering the settings, so the problem remains unresolved. Next remove the iPhone WIFI IC and test a few key points, we found that the 14 pin has no resistance value. Now we need to check the iPhone CPU , which is very complicated. There is no Bus reset signal, the normal is 1.8V, we are going to borrow it from another place, and there is a 1.8V beside it. It's useless if we directly connect it, so we need to find a resistor to pull it up