How do I know which wires to cut in alarm systems?

Solution 1:

There is actually a red box on the wall that is outside of each room where there is an alarm, It's not always directly adjacent to the room. Once you open it, it reveals which color wire and the shape that you need to cut. You may have to backtrack in order to find the alarm box.

Solution 2:

There is no way to know which wire to cut.

Furthermore, I suspect there's no "correct" wire and alarm will be triggered no matter what as I've tried many times in different cases and was never once able to guess the "correct" wire.

There is an "alarm jamming device" featured later on in the game and I kept hoping that it will become available as tool / equipment / skill at some point, but I've finished the game and that did not happen.

Solution 3:

I agree it appears to be random and so far there is no tool they give you to bypass the alarm. However, if you cut the incorrect wire they give you a couple seconds (you'll see a quick countdown timer) to cut the rest of the wires and that's how I've been able to stop the alarm.