It's different on every playthrough.
Go to the charging station, and wire up the hexa-pal in a half-circle going from the top peg clockwise to the bottom peg. Put it on the station. It will show the symbols corresponding to the beginning and ends of the wires. The first pair of symbols is the beginning and end of the blue wire, the second pair is for the yellow wire, and the third pair is for the red wire. If you wired it up like I described you can write down which peg each symbol stands for. Think of it like a clock. So write down the top left symbol as 12, since you started at the top, write down the top right for 2, then the middle right for 4, and the bottom right for 6. Then wire it up the same way on the left side, going clockwise from 6 to 12. The symbols will now show top left for 6, top right for 8 middle right for 10, and bottom right for 12. Once you've written down all the symbols for the positions on the "clock", just use that as a key to decipher the wiring codes in the game into actual wirings.
Remember, when you wire things, the direction matters, and the blue wire goes first, yellow wire second, and red wire last.