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Repair: iPhone 6 Display Failure After Replacing Battery

We are going to repair iPhone 6 with display failure, we get to know from customer that the situation happens after the battery was replaced. Why this happens? How should we test and repair?
The iPhone 6 works normally before the battery is replaced, but the iPhone is not displayed after the battery is replaced. This fault is usually due to the client accidentally installing the long screw in the short screw position and then the screw under the circuit. It was pierced.

Opening the iPhone and remove off the iPhone motherboard. Measure the resistance value to grounding for display socket J2019 with Fluke 15B+ Digital Multimeter, we find the resistance value to grounding for 14 pin AP_TO_LCM_RESET_CONN_L is infinitely large, which is clearly disconnected.

There is the trace of a breakdown for left screw column BS2502 after observing it under the HDMI Camera Stereo Zoom Microscope, scrap it and re-connect the disconnection. Measure the resistance value to grounding for display socket J2019 14 pin AP_TO_LCM_RESET_CONN_L with multimeter, the data is normal.

Install the iPhone and test it, we find the iPhone volume button not working, and the WIFI cannot be recognized.

Measure the resistance value to grounding for iPhone volume button socket J0802, it is infinitely large, and perhaps it is disconnection. This circuit line is on the third floor of the left screw column that near the edge position, carefully scrape it and then re-connect it.

There are 2 reasons why WiFi can not be identified, one is the iPhone motherboard is disconnected, the other is the iPhone WiFi module IC problem. Remove the iPhone WiFi module IC and measure the effect of resistance on the grounding of the pad, no abnormal was found. Replace the new iPhone WIFI module IC, install iPhone and test it.

Both the iPhone volume button and WIFI functions are normal now, repair ends up here! If you want to get more information about cell phone repair, please check on www.vipfixphone.com

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