The second trial is at an empty electric power plant. The front gates are locked, so you'll have to find another way in. You can either head to the right and climb the rubble over the wall by the white butterfly painted on the wall, or go around the lot the other way, until you come to a hole in the fence. After climbing up the rubble with a set of combo instructions, hop down to the yard in front of the building. The front door to the building is locked, so keep going to the other side where the chain link fences are. The first fence requires combo instructions, as does the one on the other side of it. You'll end up in a yard full of arcing transformers. This is the same yard you'd come to if you entered through the hole in the fence going the other way from the beginning.
If you came in over the wall and through the fences, switch your camera so you looking at Ethan from far away and you'll see the white butterfly symbol on the brick wall there. If you came in the other way, the door by that butterfly is ahead and to the left of where Ethan is facing when he enters the yard. Either way, head to the symbol and enter the door next to it.
Through the tunnels
Inside, walk over to the opposite end of the little room, and turn the wheel by tapping . Open the door to the long, dark tunnel and pick up the match book sitting on the ledge. Strike the match to peer in, then climb up with some combo instructions. Crawl down the tunnel using like you would if you were walking, and eventually you'll run into a bunch of broken glass. You'll need to crawl through the maze of tunnels that are filled with broken glass. If you're not on the easy difficulty, you'll need to stop moving when you see the red flares on the sides of the screen. If you keep going Ethan will finally say something about how he needs to stop, and then if you don't he'll pass out. You can fail the trial either by taking too much damage or by taking too long.
When you get to the first intersection, you'll have to light a match and watch it get pulled to the source of fresh air. This is how you can navigate through the tunnels, by checking the direction the flame is being pulled at intersections. The first intersection also has a white butterfly in the direction you need to go, in case you weren't paying attention to the flame. When making turns in the tunnel, make sure to hold and the direction you want to go with . The second and last intersections also come up dead ends where you have to turn, but the third one doesn't, so pay close attention after the second intersection so you don't miss the third one.
Through the wires
When you make it out of the tunnels, you will slide down a chute to a field of electrified transformers and the table with the memory card on the other side. The way through the maze of electrified wires can be found by looking for wires that aren't spitting blue electricity from them. Of the five entry points to the maze, only one is safe to start with, and to make it through you'll need to hold down combo instructions. Be ready to tap a button also, as in the middle of the maze you'll have to repeatedly tap a button while holding the others to get through. Whenever you make it to the other side of a set of wires, change the view to look at the maze as a whole so you know which way to go, then change it closer to see which direction isn't electrified.
If you mess up while crossing a set of wires, you'll be burned and the same jagged red flares will appear on the sides of the screen. This time however, they don't go away if you rest, so you can only take damage a couple times. When you get to other side, any movement will take you over to the table where you'll get another memory card and unlock a couple more letters to the puzzle. You can fail here by getting zapped too many times, or by walking out the door marked "Coward" on the starting side of the electric field.