2009 Smart Car DOESNT START

HELLO. I VE SEEN YOUR VIDEOS ON INTERNET AND YOU IMPRESSED ME. I HAVE A GARAGE IN MY HOME AND I AM WORKING PART TIME WITH FRIENDS. A SMART FOR TWO PURE CDI DOESN'T START. THE ELECTRIC PUMP SENDS FUEL TO THE HIGH PRESSURE PUMP AND ALSO FUEL COMING TO THE COMMONRAIL AND TO THE FUEL INJECTORS PIPES. I BELIEVE THAT THE PRESSURE IS NOT ENOUGH. IVE CHECKED THE WIRES COMING FROM THE ECU TO THE PRESSURE SENSOR ON THE COMMON RAIL AND I FIND OUT THAT THE VOLTAGE REFERENCE WIRE IS 5V AND THE GROUND WIRE IS OK. THE SIGNAL WIRE IS ALSO ABOUT 5V. IS THAT NORMAL; WHEN I PUT BACK THE WIRES ON THE SENSOR I HAVE 5V REFERENCE, NORMAL GROUND KAI 0.3V SIGNAL. DO I NEED TO CHANGE THE PRESSURE SENSOR OR IS THE PRESSURE REGULATOR SWITCH. PLEASE CAN I HAVE YOUR OPINION. I PROMISE YOU GONE HAVE YOUR DONATION LATER. THANK YOU. I WILL BE CLOUD TO COOPERATE.