Bushwhacked - S1-E2
Continuity mistake: When Kaylee and Simon go looking for spare parts on board the derelict ship, there are two green lights lit up on a control box behind Kaylee. But once Kaylee pulls one of the ship's parts out, the two green lights are no longer lit. Several lights in the room flicker and flash on/off, but the two green lights on the control box behind Kaylee do not.