Diagnosis And Testing - Fuel Level Sending Unit

The fuel level sending unit contains a variable resistor (track). As the float moves up or down, electrical resistance will change. See ANALOG INSTRUMENT PANELS - LIBERTY article for Fuel Gauge testing. To test the gauge sending unit only, it must be removed from vehicle. The unit is a separate part of the lower fuel pump module section. FUEL PUMP MODULE  for Removal/Installation procedures (remove only the upper section of the fuel pump module). Measure the resistance across the sending unit terminals. With float in up position, resistance should be 20 ohms (+/- 5%). With float in down position, resistance should be 270 ohms (+/- 5%).