We disassemble the battery, use the latest iPower DC power supply cable to detect the charging current, but we found it still keeps jumping, connect to the LCD screen, no any display shows.
Next, disassemble the machine and connect DC Power Supply, we find no current. There is no leakage on the front side, triggering a large current, which reaches 1.9A. Then, it’s easy to spray rosin to power on, current appeared.
Picture 1
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 referred to is NAND flash at first. Click a few points, we thought this point probably have fault, and measured it, it is the fault one.
Picture2
The next step is simple. Use the iphone Scraper to remove the power supply capacitors around the NAND flash. Plaster on rosin, adjust the current meter to 3V and operate directly.
Picture 3
We found this capacitor shorted and use the crowbar to open it.
Picture 4
Then test it ,we found that there is no short circuit.Turn on and test the battery's electric light is shine. Put it on the activation board and add some power, then turn it on again.
Picture 5
There should be no problem here, we should notice: it is not necessarily that the hot one fault. I think that many people will move the main power supply when repair this iphone. But my advice is to check the circuit diagram with WUXINJI Dongle to test if the power supply is short-circuited. Such short-circuits outside often occur. Many of the first pictures are short-circuited by the main power supply itself.
No comments:
Post a Comment