Some friends reported that it is difficult to observe whether the circuit board is burned out, because it is not as obvious as being broken. We can observe whether these components such as capacitors have turned black. If there are such traces, it means that the current is too large when used before. Big. The resistance of components like resistors cannot be observed. In this case, tools are needed for inspection. Multimeters are commonly used measurement tools. If damage is found, they should be replaced in time.
In the circuit board repair, the integrated circuit part should also be paid attention to. If there is a bulge, it must be burned out. If it is black or cracked, it is also a burn out phenomenon. In addition, there are two manifestations of burnout, one is that the circuit board will appear to be peeled. The second is that the fuse has blown. Of course, we can also use a multimeter to detect it.