OPPO R9S Plus black screen plus touch failure (virtual welding of power supply output inductance)

OPPO R9S Plus black screen plus touch failure (virtual welding of power supply output inductance)

OPPO R9S Plus, the fault is black screen plus touch failure. Take the motherboard out for testing. Since it is a touch failure of the black screen, let’s first check whether the appearance and resistance of the seat display seat are normal. After testing, we found that there is no missing piece near the seat, and the resistance values are also normal. We also measured the display power supply and backlight power supply, which shows that it is not a display problem. At this time, we need to think differently ……See below for details:

[Fault model] OPPO R9S Plus

[Fault phenomenon] Black screen and touch failure

[Maintenance process] I received a machine sent by a customer for repair, the model is OPPO R9S Plus, and the fault is black screen and touch failure.

In this way, we first replace the screen to eliminate the external configuration, and then consider repairing the motherboard. After changing to a good screen, we found that the fault is still the same, which means that it is not a screen problem. We took the motherboard out for testing. Since it is a touch failure of a black screen home, let’s first check whether the appearance and resistance of the seat display seat are normal. After testing, we found that there are no missing parts near the seat, and the resistance values are also normal. The display power supply and backlight power supply are also measured, which means that it is not a display problem. At this time, we need to think differently. Most of the ups and downs are caused by the virtual welding of chips or components. However, when measuring the resistance of the display seat, we didn’t find any obvious resistance value that is too large or too small. Let’s look at the power supply, because the common fault of R9S Plus also has a black screen caused by the virtual welding of power supply or inductance. The air gun blows for a few seconds near the power supply when it is turned to 200, and an inductor falls off when it is picked with tweezers. Check it out.blueprintIt’s L4002. This inductor is soldered.

OPPO R9S Plus black screen plus touch failure Figure 1

Find a rich inductor to flatten the pad, and then start the test. After half an hour, there is no black screen, indicating that the fault should be repaired, and then continue to test the stability.

OPPO R9S Plus black screen plus touch failure Figure 2

[Maintenance Result] Install the motherboard into the shell.mobile phoneIt can be turned on normally, and the functions of WiFi, Bluetooth, voice, charging, fingerprint, taking photos and making phone calls are all normal, so the maintenance is over.