Restore the Fire of the Mountain (3) | The Fire of the Mountain Darksiders 2 Guide

Use the north door and pass through the unguarded corridor, finding a chest on the way. When you reach the main chamber on the floor, start with getting to a small area on the right, where you'll find another chest. Apart from that, there's a also a Book of the Dead page here ([Book of the Dead] side quest]).

When you're done, interact with the switch shown on the above screen, moving counter-clockwise. If you do it properly, the game will trigger a cutscene in which the mechanisms becomes active again.