DTC P0461: Fuel Level Sensor Malfunction: Description

Fuel level sensor changes resistance in response to fuel level. Powertrain Control Module (PCM) monitors signal circuit of fuel level sensor to determine fuel level. When fuel tank is full, sensor resistance is high and PCM senses a high signal voltage. When fuel tank is empty, sensor resistance is low and PCM senses a low signal voltage. PCM uses signal circuit of fuel level sensor to calculate percentage of remaining fuel in tank. PCM sends fuel level percentage through class 2 serial data circuit to Instrument Panel Cluster (IPC) to control fuel gauge. Fuel level information is also used for misfire and EVAP diagnostics. This diagnostic tests for a stuck fuel level sensor signal. PCM stores this DTC if fuel level sensor signal appears to be stuck based on a lack of signal variation expected during normal operation. DTC will store when PCM does not detect a change in fuel level of at least 0.79 gal over a distance of 200 miles. When DTC is stored, fuel gauge defaults to "E". A FUEL LEVEL LOW message illuminates in Driver's Information Center (DIC), and PCM records operating conditions at time diagnostic test fails. PCM stores failure information in failure records. DTC becomes a history when conditions for storing DTC no longer exists. A history DTC clears after 40 malfunction free warm-up cycles.