Repair Guide: iPhone 6 doesn’t display after replacing screen

When we replaced the iPhone 6 display screen, press the iPhone power button, the iPhone turning on, but the iPhone LCD screen doesn't display.  We need to fix it, here is the repair guide!

Disassemble the iPhone, and take out 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 causes the WIFI cannot be recognized, one is the iPhone motherboard disconnection, and the other one is iPhone WIFI module IC problem. Remove the iPhone WIFI module IC and measure the resistance value to grounding for solder pad, no abnormal was found. Replace the new iPhone WIFI module IC.

Assemble the iPhone and turn it on, the iPhone screen displays normally, and check iPhone volume button and WIFI function, all works properly, the iPhone 6 has been repaired.