Have you ever been faced with a piece of equipment that either doesn't work as it should or has stopped working altogether?
There are several strategies that can be employed by anyone, in an attempt to diagnose the problem either to be able to describe it to a repairer or if suitably skilled, repair it yourself.
But this particular post is NOT about how to repair something, instead it outlines the steps that can be taken to help determine the nature of the problem.
It may sound like stating the obvious but if you know that the equipment used to work perfectly but now doesn't, then you're halfway to a solution! At least you KNOW the problem is not one of faulty manufacture or missing parts, etc!
Next, there is the concept of SYMPTOM, FAULT & CAUSE. Just as your GP may ask you what symptoms you have when presenting with an illness, etc. so it is with faulty equipment.
Take for example, a vacuum cleaner that one day decides to stop working. In this case, the SYMPTOM is that its motor fails to run; nothing happens when you switch it on.
In situations such as this, many people will check the fuse in the plug, perhaps by substitution with a new one. You switch 'on' and the motor now runs, indicating that the FAULT was a blown fuse. But what caused it to blow?
Perhaps you notice that the cleaner appears to be labouring? You switch 'off' and check the brush roller and discover it clogged with fibres that are restricting its rotation, making the motor work harder, which draws more current that eventually blows the fuse. The CAUSE was a clogged brush roller.
How does all this help anyone? Well, in different circumstances, being able to describe a problem correctly greatly assists the person whose job it is to identify the CAUSE of the problem, just like your GP!
Another technique that may be employed in diagnosis is exemplified by imagining watching a magician, conjuror or illusionist. When you see a performed trick that is not obvious how it's done, many of us simply think, 'well, I wonder how he/she does that!'
The chances of figuring out how the trick is done is less by this approach than if instead we asked ourselves, 'what would the conjuror have to do to create that effect?' This latter stance may bring us nearer a solution.
The same kind of thinking can be applied to a faulty piece of kit by asking yourself, 'what had to happen to create this symptom or fault?' You still might not arrive at a solution but it's worth a try!
Finally, an engineering axiom:
'Faults in mechanical systems are usually found in minutes but take hours to repair, whereas faults in electrical systems can take hours to find but perhaps only minutes to repair!'
If any of this waffle has been of use to anyone, I may be inclined to offer a sequel!
Be safe!
