Circuit/System Description

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