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Repair Guide: iPhone 6 Plus Touch Failure


We received the iPhone 6 plus, the customer described the failure as the iPhone 6P the ground, and the iPhone 6P did not respond to the touch. As you all know, M1 pin easy to disconnect is a common fault for the iPhone 6P, whether the iPhone is down or used for a long time, this should be a design flaw in the motherboard. The M1 pin is a synchronous signal from the iPhone screen to touch communication. The trouble is that sometimes the touch doesn't work at all and white lines appear above the screen.
 


Reboot to measure. After turning on iPhone, and touch and display function tested are normal. In this case, there is a way that touches this position of the front socket by your fingers (because the back is the iPhone black touch IC), if there are some problem on M1 pin, then the failure will be shown clearly. 


After testing, we start to repair.

Disassemble the iPhone, the iPhone motherboard is good, the iPhone battery has been replaced. 

Remove the U2404 black touch IC, we found the MI pin doesn't disconnect, but almost disconnect. Use BGA blade to pry the copper on the upper left corner, apply some tin on it, use QUICK 861DW hot air rework station to re-connect a copper wire to the solder pad, and then apply some green UV oil. Here is tip, with the hot air gun and ultra violetlight lamp will make it more solid, the thinner for the green UV oil, the better. 


Finally, reballing the iPhone black IC, and then install it, turn on iPhone and test it, the failure has been solved.

If you want to get more repair tutorials, please contact us on www.vipfixphone.com


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