As someone who knows next to nothing about electronic components, can you provide some example inputs and outputs? Without knowing what the exact problem is, it's hard to determine feasibility.

Off the top of my head, if the symbolic language is quite simple (i.e., every symbol acts more or less independently of each other, so you can just tack the text for what each does one after another), you can essentially do this with optical character recognition or some computer vision approach and just use a simple set of rules to translate each visual detection into text. If the language of how these diagrams work is more complicated than that, though, it may not be so simple.