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Guide: iPhone 6 Touch Function Failure

The iPhone 6 fault is that the touch can't work completely, it should be iPhone white touch IC problem. After removing the motherboard, we found the iPhone black and white touch IC have been replaced by former repair man. Measure the working condition for iPhone black and white touch IC, and measure the 5.1V and 1.8V of the iPhone white touch IC. 



The iPhone black touch IC +5.7V -5.7V and 1.8V power supply.


After measure them with digital multimeter, all the data tested is normal. Remove the iPhone black and white touch IC, and then measure the diode data for the solder pad, it is normal.

Based on previous maintenance experience, we know that the inductance of the iPhone 6 plus the display socket synchronization signal is easy to be null welded and causes the iPhone to not touch at all. The measured value of the socket synchronization signal in iPhone 6 is about 400, which is normal. With this fix in mind, we replaced the new U2403 touch sync tube and then turned on the iPhone to test it, but the problem remained.

Remove the touch synchronizing tube, then measure the 6 pin earth resistance, about 700, which is normal data. When measuring the first pin, we found an anomaly, the resistance of the pin is infinite, and the normal data should be about 400.


Check iPhone schematic diagram through the WUXINJI Dongle, we know that this pin is connected with a test point PP2405, the data of PP2405 tested is 400, which is normal, so we decided use QUICK 861DW hot air rework station to solder the jumper wire between PP24005 and the first pin on the synchronous tube .


After welding and installing synchronous tube, open iPhone and enter iOS for testing. Now iPhone touch failure has been repaired.

More professional cell phone repair information check on www.vipfixphone.com

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