Faulty model: iPhone 6 Plus
Fault description: automatic restart from time to time
According to the customer’s description, the machine is faulty for irregular automatic restart. Connected to the ammeter charging, found that the current is 0.05A, basically no current, is not charging.
At first, I thought it was USB and charge management chip problem, first disassemble the motherboard, and connect the USB management chip and charge management chip around. The capacitors, resistors hit the ground value, and found that the ground value are normal. Then measure the tail plug whether there is a 5V power supply output, 5V power supply is also normal.
Customers since the restoration of factory settings, the first brush in the boot test, boot, prompt does not support this accessory, and let me boot suspected Is not USB bad, test and online video and other functions are normal, no reboot. Pick up the machine first to open the screen a split second, suddenly reboot, is the battery holder contact bad? Quickly look under the microscope, scrape a bit of the test foot copper with a pair of tweezers, then load the battery and turn it on.
After an afternoon test, no reboot phenomenon found again, the fault is perfectly eliminated.