iPhone 8 Plus Turn on With Black Screen Repair

Phénomène de dysfonctionnement

There is no response on the screen when is turned on the phone.

Dépannage

For the iPhone 8 Plus Turn on With Black Screen Repair issue.

Take apart the phone and connected with DC power supplies, press the power button to power it on, the reading on the ammeter is normal.

So we need to check the display touch connector J5700, the measured diode value of pin 39 and pin 45 on J5700 is OL, which is abnormal. Judging by this, the fault is related to the relevant circuit of the two pins.

According to the circuit function block,

• pin 39 on J5700 is connected with pin A1 on U5650 via R5730
• pin 45 on J5700 is connected with pin A1 on U5660 via R5733

So we should check the R5730 and R5733, the measured value is abnormal. Judging by this, we can conclude that the R5730 and R5733 have been damaged.

Replace the two resistors with new ones, then assemble it and test again, the screen can be lit up, problem resolved.

Cours de réparation de la carte mère de l'iPhone X