The circuit board is broken. It can be repaired basically
If there is only visible component damage, replace the component. If the circuit board is broken, and the circuit board can’t see any damage, we should check the working conditions of each part according to the circuit diagram, and use the universal meter to check whether the current of the circuit and the resistance and voltage of some components are normal, so as to find out the causes and repair the fault. If there is a large short circuit in the circuit board, the burning machine method is used to find the hot components and find the short circuit point. Sometimes the components do not know whether they are good or bad, so they can only be replaced one by one until the voltage or current of the circuit board returns to normal, so as to find the damaged components. If you are lucky, you can find the fault at once. If you are not lucky, it will take a long time.
If the circuit board is directly broken, or the circuit board is corroded, there is a drop point, broken wire and so on. This is a test of the technician’s skills. At this time, it is necessary to connect the wires or fly the wires directly. Scrape open the circuit board for wiring, or find a pin with the same voltage to fly a wire directly. Some circuit boards break directly, especially when there are too many layers, they need to be scraped off and connected layer by layer.
Repair circuit board to consider the cost of maintenance and circuit board value
In some cases, when the maintenance cost is high, it is not recommended to repair, but directly replace the circuit board. In addition, we should also consider the technical problems of the maintenance personnel, especially the circuit board can not find any fault, and it is more expensive to replace the circuit board. It is better to replace the circuit board with another shop for maintenance, rather than choose to replace the circuit board.