跳至主要内容

Solution: iPhone 6 Won't Turn on

We are going to fix an iPhone today, according to owner's description. the device was dropped once then it's unable to turn on and overheating. How to solve this problem step by step? Let's find solution in the article.

Step 1

Disassemble the iPhone 6 by JM-P01 Essential Toolkit, take out the iPhone motherboard and measure it with DC power supply, it shows large current when booting, about 1300mA.


Step 2

The boot current shows about 1300mA, which is abnormal. Put the iPhone motherboard under a VGA Camera 7-45X Trinocular Stereo Microscope to observe it carefully, we found the culprit on the motherboard. There is a capacitor has been penetrated, which caused the iPhone to turn on with an abnormal large current phenomenon.


Step 3

Now, we've decided to dismantle this capacitor. With the help of Hot Air Gun and Precision Titanium Alloy Tweezers, we succeeded in tearing down this capacitor. Using Fluke 15B+ Digital Multimeter to measure it, the diode data shows more than 300, it is normal. This circuit is iPhone Nand flash power supply 3V, PP3VO_NAND short circuit will causes iPhone won't turn on, and the boot current up to 1000mA.


Step 4

After removal, measure it again with 1503D+ DC power supply, the boot current is normal now. Install the iPhone well, and the press the iPhone power button to turn it on, now the iPhone 6 can turn on normally and smoothly into IOS.

More cell phone repair information read at www.vipfixphone.com

标签：

评论

发表评论

此博客中的热门博文

iPhone 6 Display Failure after Replacing LCD

The iPhone 6 display is black after replacing LCD. After checking, the diode data of display socket is normal and all power supply for iPhone display IC  output is normal. Testing by  DC power supply , we find the iPhone current is abnormal. When press the iPhone power button, the boot current is obviously large. The current reached 100mA when press the power button. After remove the display tube, the current still the same, which means there is a short circuit. Measure the voltage output of each circuit of power supply with Fluke 15B+ Digital Multimeter , then surprised to find that there are really short circuit places. LD010 is short circuit; we suspect that the filter capacitance on the circuit has been penetrated. After remove the iPhone power control IC , we found it is ground short circuit. Open the WUXINJI Dongle  to check the iPhone schematic circuit, we found that this circuit is the display card image transmission MIPI data bus power supply. CPU brea...
发表评论
阅读全文

Solution: Why iPhone X Voltage Keeps Jumping

After getting the iPhone X motherboard to test, we observe the current value repeatedly jumps between 0mA and 50mA on DC power supply , and it is different from the normal booting current. Next, test whether the power supply of every circuit is normal. PP_VDD_MAIN is measured 4.2V; PP_VDD_BOOST measured is 4.2V. PP1V8-ALWAYS is 1.8V, all the values are normal. But when testing PP1V1_S2, PP0V8_SOC_FIXED_S1, PP1V8_S2 and other circuit voltage that output by power chip U2700 voltage are jumping constantly. According to previous experience, voltage jump is usually caused by a power supply circuit of U2700 output. Measured with digital multimeter , there is no short circuit was found for the dipole value of all power supply to ground. We repaired iPhone 7P before and know that if crystal oscillator is false welding can also cause voltage jumping, And if iPhone CPU  power supply is abnormal also can cause voltage jumping. Check the crystal oscillator we find no problem, then check th...
发表评论
阅读全文

Guide: iPhone 7 Plus Camera Fault Repair

iPhone camera failure is common for most of cell phone repair technicians, today, we're going to fix iPhone 7 Plus camera. According to the holder's description, the front small camera is normal while the rear camera fails to take photos, when turn on it, the iPhone 7 shows black screen. Let's start from easy repair operation: directly replace the iPhone camera to have a test.  Note: Pay attention that two camera are connected together. When disassemble the iPhone 7P rear camera , you need to pry up from the left side.  The fault is same as before after replacing a new rear camera. We tested before, the iPhone 7P double camera is rely on the bigger camera to get image, as shown in 15-5-1, the corresponding part on iPhone 7P motherboard is J4501 pin, the resistance value is normal after testing with Fluke 15B+ digital multimeter , it reminds of us that iPhone6 Plus also encountered this phenomenon, the power supply part has some problem. By checking on  WUXINJ...
3 条评论
阅读全文