On the off-chance you have not figured this out by now, and just in-case someone else comes by looking for this answer, I doubt it but.. maybe, I'll go ahead and answer this question.
You grapple the relay with your arm (which if you've made it to a relay you know how to do) and then press the light punch key (default F on keyboard/mouse setup).
--------------------------------------------------------------------------- Unwinding is the mortal coil, that drives the gears to tick and toil, until at last, it rests, unwound, and we lay silent in the ground.
Haven't tried this PC version yet - came to get the trainer first, as I've been waiting for the PC version after I got and finished the PS3 version a month or so ago. I wish there were cheats for the PS3 version!
However - surely the tutorial is still given to you near the beginning of the game - which tells you exactly how to "hack" the relays... it's not a secret or anything - there's no real "hacking" or anything even remotely tricky going on - it's just like moving or punching or whatever, just hit the button and it's done, no?
Cheers
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