iPhone 6 screen display abnormal repair

Machine model: iPhone 6

Malfunction: the screen display of the mobile phone is abnormal.

Maintenance process: remove the motherboard and observe with microscope. There are a lot of Flux on the touch pad of the display pad.

iPhone 6 screen display abnormal repair Figure 1.

Cleaning solvent was cleaned, and by the way, J2019 showed that 1 pin PP_LCM_BL_CAT2_CONN and 4 pin PP_LCM_BL_CAT1_CONN on BTB connector were against pin, and found that 4 pin pin was 2111, which was abnormal and normal.

iPhone 6 screen display abnormal repair Figure 2.

Test Diode value is normal after connecting fl2025 Fuse Inductor short-circuit.

iPhone 6 screen display abnormal repair Figure 3.

The screen test showed apple but the backlight still didn’t light up. When I saw that the CPU shield cover had been moved, I removed shielding cover and found that I had made a CPU. It should be that when I blew the CPU, I blew the U1502 backlight chip Inveracious Soldering, and the periphery of the CPU was covered with Flux tin beads, which easily led to the motherboard Short circuit.

iPhone 6 screen display abnormal repair Figure 4.

Remove the backlight chip after removing the tin bead Flux. A good way to remove the backlight is to remove the three filters Capacitor above the backlight, and then it’s easy to cut.