FUEL TANK PRESSURE SENSOR RATIONALITY TEST FOR A PHEV

摘要

A method for verifying the reliable operation of a fuel tank pressure transducer positioned within a fuel tank of a PHEV. The method detects the initiation of a refueling cycle, which leads to opening a system vent valve positioned between a carbon canister and a system vent, and opening a fuel tank isolation valve. A controller monitors fuel system pressure within the fuel tank and at the vent valve, and that device determines rates of change of the fuel system pressure within the fuel tank and at the outlet vent. Reliable operation of the fuel tank pressure transducer is indicated upon a determination that the rates of change of the fuel system pressure in the fuel tank and at the outlet vent are uniform within a predetermined range.

主权项

1. A method for verifying the reliable operation of a fuel tank pressure transducer positioned within a fuel tank of a PHEV, comprising:
detecting the initiation of a refueling cycle; opening a system vent valve positioned between a carbon canister and a system vent; opening a fuel tank isolation valve to depressurize the fuel system; monitoring fuel system pressure within the fuel tank and at the vent valve, the monitoring being performed by a controller; determining the rates of change of the fuel system pressure within the fuel tank and at the outlet vent; indicating reliable operation of the fuel tank pressure transducer upon a determination that fuel system pressure at the outlet vent rises to the level of fuel system pressure indicated in the fuel tank, and that the rates of change of the fuel system pressure in the fuel tank and at the outlet vent are uniform within a predetermined range.