DTC P0461: Fuel Level Sensor Circuit Performance: Description

Fuel level sensor is a variable resistor that varies resistance according to changes in level of fuel in fuel tank. PCM supplies a 5-volt reference through a pull-up resistor to sensor, which is connected to ground. When fuel level in fuel tank is high, sensor resistance is low (low voltage on signal line). As fuel level decreases, sensor resistance increases (voltage increases on signal line). PCM uses signal voltage to determine fuel tank level. PCM averages fuel level over time, then sends it over Class II link to BCM. BCM averages fuel level with respect to vehicle speed, then sends out a message to instrument panel cluster for fuel gauge over link. DTC sets when signal voltage at PCM. DTC sets when signal voltage at PCM does not change a calibrated amount after vehicle has been driving a long distance.