Find switch in sewers is a mission in Jak 3. The Freedom League needed the floating KG war factory shut down, but the only way in was to find the cipher glyph to the old Krimzon Guard door systems which were hidden within the main room of the power station. Onin revealed the eco grid inside the main room could help them, but to get inside they would need to find the junction box inside the Haven sewers to de-activate the electric fence at the entrance.