Well, you know this new poetry. It isn't expected to rhyme or necessarily have meter. I think the Beatniks started the style in their dark, cellar bars, a poet on stage with a guy on a bass fiddle and a drummer, the audience snapping their fingers in applause, saying, "Cool, man, cool!"
What's needed here is not so much an understanding of digital fault finding but an understanding of digital systems instead. For example, a little understanding of how a binary-counter works should reveal some clues as to how you would go about fault-finding on it. And that's the same for all of the digital systems mentioned above.
Do you think the first step is to see if its got a pulse on the inputs, outputs,clocks and voltage on VCC
Because mostlys the faulty digital componet will not have a output pulse
But most Digital PCB have all these digital componets i listed and any one or more can have faultys and i don't know how to troubleshoot,test,check these digital components