Patent ID: 7127941

Claim:
A diagnosis system for a Liquefied Petroleum Injection fuel pump that determines the operation state of the fuel pump by analyzing a signal inputted from a fuel pump driver of a Liquefied Petroleum Gas tank into an interface box, the system comprising: a fuel pump relay for providing power to the fuel pump and cut-off solenoid valves; a Liquefied Petroleum Gas switch for isolating a fuel supply and configured to be operated by a user; a first signal line connecting the fuel pump relay and the Liquefied petroleum Gas switch; a voltage detector disposed in the interface box for detecting a voltage, wherein the voltage detector is connected to the first signal line and the voltage detected by the voltage detector indicates whether the Liquefied Petroleum Gas switch is on or off; a second signal line connecting the fuel pump driver and the interface box; and an Electronic Control Unit of the interface box configured to determine whether the second signal line is disconnected, wherein the Electronic Control Unit is also configured to analyze the voltage detected by the voltage detector.