Circuit/System Description

WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

The fuel level sender changes resistance in response to the fuel level. The engine control module (ECM) monitors the signal circuit of the primary fuel level sender and the secondary fuel level sender in order to determine the fuel level. When the fuel tank is full, the primary and the secondary fuel level sender resistance is low and the ECM senses a low signal voltage. When the fuel tank is empty, the primary and the secondary fuel level sender resistance is high and the ECM senses a high signal voltage. The ECM uses the signal circuit of the primary and secondary fuel level sender in order to calculate the percentage of remaining fuel in the tanks. The ECM sends the fuel level information via serial data circuit to the instrument panel cluster (IPC) for display in the fuel gage.