iPhone 6 plus Parts Screen Can’t Work

Recently, one customer send a iphone 6 plus. When after turning on, we find the iphone 6 plus right display screen is black while the left normally displays, which is called Yin and Yang screen. When the right screen turns black, it still shows nothing after awakening it. Then vipprog engineer analysed and repaired. Now I will sort out the guide for you, hoping you can benifit from it.

Solution: 

1. The abnormal backlight circuit could cause the Yin and Yang screen. First let’s start from the backlight circuit. After removing the motherboard, we find that the right backlight chip is painted green UV Solder Resist and soldered a jumper wire. The wire starts from pin A1 U1580 backlight chip to the yellow point near the fingerprint socket J2118, as shown in below picture.

2. The I2C bus that left backlight chip uses and the I2C bus that right backlight chip uses are not the same circuit. The left one is normal while the right one is not, even after the right backlight chip is replaced. Thus, we doubt that there is something wrong with I2C bus of the right backlight chip. The two backlight chips’ real material object are shown in below picture.

3. Observing the screw under microscope, we find that right and left screw holes are twisted through, as shown in below picture.

4. Use knife to scratch left screw hole, we find that it still connects. While the right one disconnects, as shown in below picture. Fixing the broken circuit and turn it on. Trouble is removed.