Circuit Description

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 unified meter and A/C amp. The unified meter and A/C amp sends the fuel level sensor signal to the ECM through CAN communication line. It consists of 2 parts. One is a mechanical float. The other is a variable resistor. Fuel level sensor output voltage changes depending on movement of the fuel mechanical float.

Driving long distances naturally affects fuel gauge level. This diagnosis detects the fuel gauge malfunction of the gauge not moving even after a long distance has been driven.