Circuit Description

WARNING: This page is about a different car, the 2002 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.

The fuel level sensor changes resistance based on fuel level. The PCM monitors the signal circuit of the fuel level sensor in order to determine fuel level. When the fuel tank is full, the sensor resistance is high and the PCM senses a high signal voltage. When the fuel tank is empty, the sensor resistance is low and the PCM senses a low signal voltage. The PCM uses the signal circuit of the fuel level sensor in order to calculate the total remaining fuel in the tank.

The PCM sends the fuel level percent via the class 2 serial data circuit to the body control module (BCM). The BCM converts this data and sends a fuel gage percent deflection to the IPC via the serial peripheral interface (SPI) in order to control the fuel gage. The fuel level information is also used for misfire and EVAP diagnostics.