Huawei Mate X2 has no signal and no service

Huawei Mate X2 has no signal and no service.

Huawei mate x2, the phone got water after getting wet, the speaker was hoarse, and the tail plug was changed after the sale; However, after a period of use, the mobile phone suddenly lost its signal, and the after-sales notification was a motherboard problem. After a series of problems appear, how to solve them? Then give it to our maintenance master!

[Machine model] Huawei Mate X2

[Fault Phenomenon ]No signal, no service

[Maintenance process]

I received a machine sent by a customer for repair, the model is Huawei Mate X2, and the customer said it rained a few days ago.mobile phoneI was caught in a little rain, and it seemed that I got into the water. I found that the speaker was a little hoarse at the back, so I changed the tail plug after the sale. After using it for a while, I suddenly lost the signal. After the sale, I was told that it was a motherboard problem and it would cost thousands of dollars to change the motherboard. The customer found us when he thought it was too expensive.

After receiving the machine, directly remove the motherboard for testing. For the machine with no signal in the water, the first thing we should think of is to see if there is any corrosion on the motherboard, especially the RF part of the signal, such as the power supply of RF and the power supply tube of the power amplifier. If there is a short circuit or an open circuit in the power supply, it will cause signal problems such as no service and power leakage.

After inspection, it was found that there were traces of corrosion in the power supply of a power amplifier on the signal board.

Huawei Mate X2 has no signal and no service Figure 1

The startup test found that this power supply did not come out. After testing, it was found that this power supply not only supplied power to the power amplifier, but also supplied power to the antenna switch. However, because it did not,blueprint. There is only a one-point connection, so let’s replant the chip first to see if it can be repaired, and by the way, solder the capacitors and inductors near this area again.

Huawei Mate X2 has no signal and no service Figure 2

After replanting, start the card insertion test again, and the signal has already appeared.

Huawei Mate X2 has no signal and no service Figure 3

[Maintenance result] Install the motherboard into the mobile phone, and start the test. The mobile phone is normally booted into the system, and the functions such as charging, WiFi, voice, compass, vibration and telephone are normal. The maintenance is over here.

This case was originally provided by Xunwei Quick Repair Flagship Store, and it is forbidden to reprint without authorization!