跳至主要内容

Guide: iPhone 6S Large Current When Turning On

When are going to repair a iPhone 6S today, the problem is that when we test with DC power supply, the current value is shown as picture 1. It's large current, how should we repair it? Let's check in the article!



1. According to our past phone repair experience, there is no obvious corrosion or serious pressure on the motherboard, so we first test the motherboard PP3V0, USB and NAND power supply.

2. In the maintenance process, if you encounter the same situation:  the motherboard is large current and also can be turned on, if the motherboard and above several circuit PP3V0 are all normal, you can first install the iPhone to test function, if all the function is normal, then your lips can be touched to test whether the temperature of USB is heating, the iPhone 6S motherboard we test through the lips, it is found the USB is extreme heating, so it is determined that the USB causes large current.


3. As shown in picture 3, the current is normal after removing the USB by QUICK hot air station, and all the function is tested normally after replacing USB.


Summary: This current fault is very common for iPhone repair technician, so in the maintenance process you should be carefully observe and decrease some further damage on the motherboard.

Any other technical about cell phone repair, please check on www.vipfixphone.com

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...

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...

Iphone 6S Enters DFU Mode Cannot Start Fault Repair

The customer said that he did not know what the reason was. The mobile phone has been restarted indefinitely and can enter the DFU mode. However, when the flashing machine fails to enter the recovery mode from the DFU mode, and then the mobile phone is connected to the computer for 5-10 minutes, it automatically enters the recovery mode. After we received the 6S that could not be started, we disassembled the power with iphone engraving tool and turned on the power to 100mA. First of all, check if you can connect and read the DFU mode after connecting to the computer. Wireless DFU can not exit, we can only brush the machine to view the error. Refresh Aisi and iTunes respectively. If you stuck on the progress bar for a long time, it is very likely that the error is -1. If the progress bar does not enter, you can roughly determine the probability of a CPU failure. Now we need to see if there is a problem with the hard drive. First, use DC power supply for iphone repair, the hard disk o...