Professional cellphone repair guide and high quality cellphone repair tools

One of our customers sent us an iPhone 6s. The customer said that his iPhone was turned on and showed a high current and gray fingerprint failure. It has been repaired before, but it seems to have no effect. How can we repair this phenomenon? What repair tools do we need? Test and observation 1. Test whether the fault is the same as what the customer said. As shown in following pictures. 2. Observe under the Trinocular Stereo Microscope to check whether it has been repaired before, whether it has compression deformation, water corrosion, the most important is whether the customer's description is right. Result:  we found theiPhone 6s boot current 150 mA, grey fingerprint. Look at the most obvious grey fingerprint according to the data. Use Fluke digital multimeter to test the resistance, voltage, we found it has short circuit phenomenon. Since we found the problems, so we should eliminate them one by one. Test full function (1) test full function (2...

Last week, we received an iPhone 6S that was not displayed after the iPhone 6S was launched. Trying many times is still the same result. After asking the customer, we know that the iPhone 6S accidentally fell into the water, but the customer quickly took it out, and it seems that the iPhone has not been hurt too much, because the iPhone 6S can still be opened, but it is not displayed. Do you want to know how to fix it? Please read the article below. After received the iPhone 6S, first we need to test it. Press the iPhone power button, the iPhone screen keeps black, we try to use another iPhone to call it, it works, the iPhone 6S has response, but the iPhone LCD screen still no display. We disassembled the iPhone, connected the iPhone to the DC power supply (VIP727) to test the iPhone's boot current. The current test data is normal, which means the iPhone can be turned on smoothly. Now, we confirm that the failure is that the iPhone does not display. Take out the iPhone mothe...

Last week, the customer sent us an iPhone 6S. His iPhone 6s read the card after booting and retained the signal after removing the SIM card. He needs us to repair it. Based on our past repair experience.This situation can be divided into three kinds of faults: 1. Abnormal card holder; 2. Card detection pin problem; 3. The baseband signal part problem. Let's confirm the fault first. Install the iPhone to test, we found that as the customer said, there is still a signal even if the SIM card was pulled out. According to previous maintenance experience, first we use FLUKE digital multimeter to check the resistance of each pin of the card base, especially the resistance of the card detection pin (that is, the card switch). After measuring, it is found that the card detection pin has no resistance value. At the other end of the R3401, the resistance can be measured, and the fault is determined in the card detection pin, which is broken. Solution: you can use jumper wire ...

Yesterday, the customer sent us an iPhone 6 Plus for repair. The fault description is that the iPhone 6 Plus is not displayed and there is no backlight. The iPhone motherboard has been repaired once. But the fault still exists. How can we repair it? After we received the iPhone 6 Plus, there was no obviously damaged was found on the appearance of the iPhone 6 Plus. Use phone opening tools to disassemble the iPhone, take out the iPhone motherboard. Put iPhone motherboard under the Trinocular Stereo Microscope to observe, we found the iPhone display touch IC of the iPhone motherboard, iPhone light control IC U1501 and NUT column all have been removed. Moreover, the bottom of the NUT column on the iPhone motherboard has been hit by a long screw. Use QUICK 861DW hot air rework station and BGA remove graver to scrape it, there is no disconnection phenomenon. Measuring the resistance value for the D3# layer of the iPhone display touch power supply IC U1501 by digital mul...

We received an iPad, and the customer said that the iPad has been restarted and a white apple appeared. He didn't know what to do and needed us to fix it. According to our past mobile phone repair experience, there are occasional possibilities for white apple restart: 1. inaccurate battery power 2. system 3. NAND The faults have to be ruled out one by one. After consulting customers, we get to know the iPad can be reflashed, after reflashing, the iPad still restart from time to time, checking the iPad battery power information is normal, we eliminate the possibility of battery caused. Next, take the iPad apart, remove the NAND chip and replace it with a new one, we want to see if the iPad air NAND chip caused the unscheduled restart. Rewrite the data of new NAND chip on WL PCIE test fixture , and soldering it back to the motherboard. Install the iPad to reflash, all the functions are tested normal, it also does not restart again and again, this fault is ...

We received an iPhone 6S, the customer described the iPhone vibration and ringtones working properly. This means that the iPhone is turned on and does not display the iPhone LCD screen. The customer said that the iPhone was fixed in other places before, and after a few days of use, it was destroyed again, which is the same failure. How should we fix it? We start to disassemble the iPhone, finding that the screws on the bottom are missing, after disassembling, the screws inside are also missing a lot. This is common failure on iPhone 6S, the repair idea is that the system signal interruption or the power supply and clock are unstable, and most commonly is iPhone display circuit problem. Although there are many screws missing after disassemble the iPhone, but we don't found any repair trace of repairing. Considering this iPhone has a low chance of failure，so we start to repair from the simplest way, try to replace the iPhone display assembly . After replacement, test the iPhone...

If our iPhone camera doesn't work. That feeling is definitely very bad.Our customers are in this situation. He sent an iPhone 7 Plus to us, the fault described is that the iPhone no camera, after replace the new iPhone rear camera, the fault still there.  This iPhone was repaired before, the previous phone repair shop repaired the iPhone WIFI module IC and U3301 iPhone audio IC . According to previous repair experience, we know there are 2 camera power supply transfer tube on the WIFI IC are easy to virtual weld, after remove it, and reinstall it, the failure still there. Use the digital multimeter to measure the grounding resistance of the iPhone rear camera J3001 and J4501, and the data is normal. It is also normal to test the power of the camera socket. Measure the I2C bus on J3001 and J450. When measuring the J3001 2 pin, it is found to be only 0.4V, but under normal conditions, the normal voltage of the I2C bus should be around 1.8V. Open the WUXINJI Dongle to...