The difficulty here is that it may require you to reinstall drivers or even the OS. In addition, if the hard disk fails, you can lose all your data, which is extremely annoying. To find out if your hardware is faulty, you need to run the appropriate tests - memory tests, hard drive tests, and so on. Many modern computers (and especially laptops) already contain these tests.
Reassigned sectorsSo a novice repairer should study at least a specific user manual (User Manual).
Service Manual for inkjet printerThere are also so-called Service Manuals (repair and maintenance manuals), which contain more detailed information and methods of solving typical problems.
Note that you may not receive a Service Manual when you purchase your printer.
Service Manuals are supplied only to authorized service centers, but many can be found online.
Service Manuals are most often in English, so knowledge of technical English is a plus for the repairer. At the same time, there are many online translators, which undoubtedly makes life easier for beginners.
But the top flight is a component repair!
That is, replacing not the whole component part of the computer, but some parts on it, such as transistors or capacitors on the motherboard or in the power supply. What does it do? With the right skills, the repair can be much cheaper, since a transistor or capacitor costs much less than a motherboard or power supply.
But to get to that level, you need to know a lot more than all of the above! You have to know electronics at a good level and know how to use measuring instruments. This, too, is covered on this site, particularly in the "Electronics" section.
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