Fuel Gauge
WARNING: This page is about a different car, the 2002 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.
Fuel gauge operation in a CNG or LPG bi-fuel vehicle behaves similarly to a standard gasoline fuel gauge. The fuel gauge provides a linear reading from full to empty. Fuel gauge operation for an LPG bi-fuel vehicle is based on a float type sensor measuring the level of liquid propane in the fuel tank(s). Fuel gauge operation for a CNG bi-fuel vehicle is based on pressure and temperature of natural gas in fuel tank. On CNG models, a full fuel gauge reading will occur at a pressure of approximately 3600 psi (24,800 kPa) at a temperature of approximately 70°F (21°C). On all models, the instrument cluster is connected to SCP BUS(+) and BUS(-) circuits.