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How to Fix iPhone 6S Stuck On White Apple


The iPhone 6S fell into the water before, then it was stuck on the white apple logo after rebooting. It has been repaired once, when we receive it, iPhone 6S reboot occasionally in white apple state. After removing the logic board, we found that the iPhone U2 IC and tube have been replaced.

First of all, we decide to use 3.5X-90X Stereo Zoom Microscope 14MP HDMI Camera to check motherboard, there are small beads around the chip, which is a serious mistake. Clean up the iPhone logic board and then replace the new U2 IC and charge tube, but the problem still the same, iPhone stuck on white Apple logo and restart occasionally.

Measure the diode data for iPhone battery detective pin with Fluke 15B+ Digital Multimeter, the data is normal, the resistance of iPhone booting condition is normal, and the voltage also is normal.

For water damaged iPhone,iPhone system is less damaged. After confirming to customer, we start to flash iPhone. Connect iPhone to computer with iPhone lightning cable, the computer pop-up prompts that USB is not recognized. We suspect that the problem will be in the U2 circuit line. Take off the U2 to measure the resistance value.


After measurement, we found that the U2 IC F4 pin PP3.0V_TRISTAR is short circuit, this point is connected to power and an inductor FL5408_RF next to an iPhone WIFI module IC, the U5411_RF receive amplifier is connected to the head of iPhone logic board. In order to find the problem point correctly, first we remove the FL5408_RF, measuring the ends of the inductor, we found a short circuit at the end of the amplifier.
 


After we take off the two capacitors on the top, the problem still exist. Remove the U5411 IC and measure again, the data is normal. The glue around this chip is very soft，use QUICK 861DW hot air rework station in 150 degree to remove, but take care not to remove the capacitor next to it.


Finally, assemble the IC and re-weld the FL5408_RF to test again, the iPhone 6S turn on in a normal state now!

More professional iPhone repair tutorials read on www.vipfixphone.com

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