How to repair the circuit board? What are the steps? I just entered a company after graduating from junior college, and now I'm learning to repair the company's products and circuits with my master.

-★ 1, with all due respect: any product must have a clear understanding of the circuit structure and working principle during maintenance. If you don't know the circuit principle and circuit structure, you won't know the cause of the fault even if you detect an abnormal voltage at a certain point.

-★ 2. For example, if the voltage at a certain point is low, it may be that the stage has a short-circuit fault, or that the previous stage is not working normally: the former needs to check the fault of the stage, while the latter needs to find the reason of the previous stage.

-★ 3. There may be many reasons for the electronic product failure and the voltage change at the detection point. Therefore, the first step is to learn and be familiar with the working principle of the product and ask the masters for advice. You can pay in advance if necessary (for example, treat guests). After all, this is the hidden rule of society. Besides, there are no shortcuts.