P0461
DTC P0461
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptor
DTC P0461
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Fuel Level Sensor 1 Performance
Diagnostic Fault Information
Circuit/System Description
The fuel level sensor changes resistance in response to the fuel level. The engine control module (ECM) monitors the signal circuit of the fuel level sensor and the type of fuel in order to determine the fuel level. For regular unleaded fuel the ECM monitors a constant signal. When the vehicle has approximately 20% or greater ethanol for E85 fuel applications, the ECM controls a pulse cycle signal where it monitors the signal and calculates the fuel level percentage only during the on pulse of approximately 100 ms.
When the fuel tank is full, the sensor resistance is low and the ECM senses a low signal voltage. When the fuel tank is empty, the sensor resistance is high and the ECM senses a high signal voltage. The ECM uses the signal circuit of the fuel level sensor in order to calculate the percentage of remaining fuel in the tank. The ECM sends the fuel level percentage via the serial data circuit to the instrument cluster in order to control the fuel gauge.
This diagnostic tests for a stuck fuel level sensor signal. The ECM sets this DTC if the fuel level sensor signal appears to be stuck based on a lack of signal variation expected during normal operation.
Conditions for Running the DTC
The engine is running.
Conditions for Setting the DTC
The ECM detects a change in fuel level less than 10 liters (1.3 gallons) over a distance of 241.4 km (150 miles).
Action Taken When the DTC Sets
* The fuel gauge defaults to empty.
* The low fuel indicator illuminates.
* The ECM records the operating conditions at the time that the diagnostic test fails. The ECM displays the failure information in the Failure Records on the scan tool.
Conditions for Clearing the DTC
* The DTC becomes history when the conditions for setting the DTC are no longer present.
* The history DTC clears after 40 malfunction-free warm-up cycles.
Reference Information
Schematic Reference
Instrument Cluster Schematics Instrument Cluster Schematics
Connector End View Reference
Component Connector End Views 1-2 Shift Solenoid (SS) Valve (M30)
Description and Operation
Instrument Cluster Description and Operation Instrument Cluster
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Testing
Note:
If equipped, the following tests can be performed at an inline connector. See schematics for the corresponding terminals to test at.
1. Ignition OFF, disconnect the harness connector at the fuel level sensor.
2. Ignition OFF, test for less than 1 ohms between the fuel level sensor low reference circuit terminal B and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
3. Install a Signal Generator and Instrument Panel Tester between the signal circuit terminal C and the low reference circuit terminal B.
4. Ignition ON, vary the signal generator resistance between 40 and 250 ohms. Verify that the scan tool Fuel Tank Level Remaining parameter displays a range that varies between 5 and 95 percent as the signal generator resistance changes.
• If not within the specified range, test the signal circuit for an open/high resistance. If the circuit test normal, replace the ECM.
5. If all circuits test normal, perform the fuel level sensor component test before replacing the fuel level sensor.
Component Testing
1. Ignition OFF, disconnect the harness connector at the fuel level sensor.
2. While sweeping the fuel level sensor through its full range of motion, test for a minimum value less than 41 ohms and a maximum value greater than 119 ohms between the signal terminal C and the low reference terminal B.
• If not within the specified range, replace the fuel level sensor.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Fuel Level Sensor Replacement (Extended Cab w/26 Gal Tank) Fuel Level Sensor Replacement (Regular Cab w/26 Gal Tank) Fuel Level Sensor Replacement (Regular Cab w/34 Gal Tank) for the 4.3L engine
* Fuel Level Sensor Replacement (25 Ext/Crew Cab w/26 gal Tank) Service and RepairFuel Level Sensor Replacement (15 Reg Cab With 26 gal Tank) Fuel Level Sensor Replacement (15 Ext/Crew Cab With 26 gal Tank) Fuel Level Sensor Replacement (15 Reg/Ext/Crew Cab w/34 gal Tank) for the 4.8L, 5.3L, 6.0L, and 6.2L engines
* Fuel Level Sensor Replacement for the 6.6L engine
* Control Module References Control Module References for ECM replacement, programming and setup