What happened to the shadows on the Huawei Honor V20 screen?

With the last year popular bangs or water drop full-screen different, glory V20 uses a new phantom eye full-screen planning, is similar to the Samsung A8s dug hole full-screen planning, front camera is located directly under the upper left corner of the screen, this will be following the water drop full-screen, is likely to start this year, will be popular new form of full-screen planning.

So, the glory V20 screen has a dark shadow how? The screen shadows, in fact, appear first and foremost at the bottom of the aperture screen. In the general wallpaper, the glory V20 screen bottom dark shadow is not significant, and even difficult to be noticed. But in the white wallpaper, the glory of the V20 screen bottom shadow is very simple to see out!

Huawei P8 Youth Edition Mobile 4G Single Board Q1602 Corruption Causes No Charging, No USB Recognition

I. Description of the phenomenon, problem

The fault on the maintenance work order for the phone does not charge, plug USB does not respond.

Second, the key process, root cause analysis

1. As the motherboard for the market repair, dismantling the motherboard before doing any maintenance actions, first consider whether the motherboard is burned out or customer plug and play Damaged USB interface phenomenon, that is, the first visual inspection of J1602 (USB interface) and the surrounding components appearance, found no abnormalities.

Considering that the phone does not have any response when plugged into the USB, the motherboard fault for not charging, do not identify the USB, it is likely that USB The interface has open pins or path open phenomenon. But the measurement of the USB interface of the various pins to ground impedance, and normal board comparison are normal.

3. Since the ground impedance is normal, the motherboard is no problem with the channel, but does not mean that the motherboard voltage and power supply are normal, so view the circuit diagram , through the circuit diagram USB interface pin by pin towards the measurement of each pin path voltage.

Huawei P8 Youth Edition Mobile 4G does not charge, does not identify USB repair Figure 1

4. The measurement process and corresponding measurement points are shown in the following table.

Huawei P8 Youth Edition Mobile 4G does not charge, does not recognize USB repair Figure 2

Visible measured voltage values are also normal, but considering the VBUS_USB to charge management chip (U201) between the Also through a field effect tube Q1602, this field effect tube is to control the VBUS_USB voltage to protect U201 So we measured the voltage of VCHG (C1622) and found that the voltage is 4.23V, which can be seen after Q1602. The voltage is reduced by 0.7V. Consider the voltage reduction of the control due to Q1602 body damage.

Conclusion, solution and effect

After replacing Q1602, the phone charges normally and identifies USB normally.

IV. Summary of experience, preventive measures and standard recommendations

The two faults of not charging and not recognizing the USB are often both present at the same time, and when fixing such faults be sure to link them together for a comprehensive repair. Location. The key point of such failure is about the USB pin measurement, step by step in accordance with the pin measurement anomaly, against the wiring diagram for Find out why.

Huawei mobile phone standby time is too short

Solution: For the old mobile phone, the first thing to think about is because of battery aging this situation, you can replace the phone battery way to solve the problem, suggested to the repair place first check the specific situation, many mobile phones are now non-removable battery, or need professional maintenance personnel to solve the replacement problem, and do a good job of mobile phone backup Oh.

For the new mobile phone, you need to do the following: 1, in the use of wifi, Bluetooth, gps or data services, the corresponding functions will be turned off;

Huawei phones keep rebooting

Solution: When the mobile phone is infected with virus, installed incompatible software or unstable battery installation, there will be a constant restart. The phone should be installed with an anti-virus, kill check software, regular cleaning and killing, so as to ensure the network security of the phone, but also to solve the problem of The constant reboot due to virus.

For some mobile phones with removable batteries, you need to first check whether the battery is stable.

If the phone is restarted because of software installation, you can first uninstall incompatible software or restore the factory settings to try, if this still exists, it is recommended to refresh the phone.

Huawei’s mobile phones are heating up

This problem directly leads to burned components, minutes to change the rhythm of the new mobile phone, the performance of the mobile phone is also very serious, especially now many friends like to play a variety of hand games, such as the king’s glory relatively large mobile phone case, playing with the mobile phone hot can not, accompanied by the phenomenon of Caitton.


1, do not install poor quality mobile phone case, such products will have an adverse impact on the cooling of mobile phones.

2, do not use your phone for long periods of time while charging in the sun-directed environment, paying special attention to not playing games while charging.

3, at any time to close the background running unnecessary programs.