Description & On Board Diagnosis Logic
WARNING: This page is about a different car, the 2003 Infiniti M45. However, it is still accessible from the selected car via links, so may be relevant.
The fuel level sensor is mounted in the fuel level sensor unit. The sensor detects a fuel level in the fuel tank and transmits a signal to the ECM. It consists of 2 parts, one is a mechanical float and the other side is a variable resistor. Fuel level sensor output voltage changes depending on the movement of the fuel mechanical float.
When the vehicle is parked, naturally the fuel level in the fuel tank is stable. It means that output signal of the fuel level sensor does not change. If ECM senses sloshing signal from the sensor, fuel level sensor malfunction is detected. For on board diagnosis logic, see Fig 1 .