For tests that do not specify the use of artificial networks, the power supply shall be connected directly to the Load simulator, DUT and ground plane (power supply return). 5.3 Load Simulator DUT operation shall be facilitated by use of a Load Simulator that is constructed to simulate the vehicle environment as seen by the DUT in its installation. The load simulator is an enclosure that contains all external electrical interfaces (sensors, loads, etc.) normally seen by the DUT.