Huawei notebook does not boot (3V short circuit)

Huawei notebook does not boot (3V short circuit)

Huawei notebook, the fault is not turned on. The power-on trigger current is only a few tens of milliamps. When the main board is removed to test the major inductors, an inductor with a resistance of 0001 is obviously found. After reading the arrangement of the inductors, it is basically determined to be a 3V inductor. Because this model is relatively new … I want to know how to maintain it next. Please see below!

[Fault model] Huawei notebook

[Fault phenomenon] No boot.

[Maintenance process] I received a machine sent by a customer for repair, the model is Huawei notebook, and the fault is that it does not turn on.

Huawei notebook does not turn on Figure 1

The power-on trigger current is only a few tens of milliamps. When the main board is removed to test the major inductors, an inductor with resistance value of 0001 is obviously found. After looking at the arrangement of the lower inductors, it is basically determined to be a 3V inductor. Because this model is relatively new, it cannot be found.blueprintWe can only observe whether there is any capacitor that is obviously burnt yellow first. The motherboard is removed and observed for a circle. If there is no capacitor that is obviously damaged, let’s burn the machine and try it. There can’t be a short circuit that can’t be repaired. As a result, the machine can’t find the place where the short circuit is hot, and the thermal imaging has taken a circle of capacitors or chips that are not hot. Then we can only use stupid methods to repair it. Dismantling method, first tilt the inductor and judge whether it is a front-end or a back-end short circuit. Then remove all the short-circuited components until they are not short. This method is slow, and it depends on luck. Fortunately, our luck is not bad. When we removed the seventh and eighth one, we found that a capacitor next to the 3V inductor was broken.

Huawei notebook does not turn on Figure 2

After deducting it, put the other capacitors back one by one, and then start the test to enter the system normally.

Huawei notebook does not turn on Figure 3

[Maintenance result] The mainboard was installed, and the startup test was successfully lit. The recording, camera, sound and WiFi of the system test were normal, and the stress test of the baking machine was normal for half an hour. The maintenance was over.