P0462
Fuel Gauge Malfunction - DTC P0461-P0464
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 Descriptors
DTC P0461
-
Fuel Level Sensor Performance
DTC P0462
-
Fuel Level Sensor Circuit Low Voltage
DTC P0463
-
Fuel Level Sensor Circuit High Voltage
DTC P0464
-
Fuel Level Sensor Circuit Intermittent
Diagnostic Fault Information
Circuit/System Description
The fuel level sensor changes resistance based on fuel level. The 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 resistances of the fuel level sensor is low and the ECM senses a low signal voltage on the signal circuit of the fuel level sensor. When the fuel tank is empty, the resistance of the fuel level sensor 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 serial data to the body control module (BCM). The BCM then sends the fuel level percentage via serial data to the instrument cluster in order to control the fuel gauge. When the fuel level falls below approximately 11% the instrument cluster illuminates the low fuel level indicator.
Conditions for Running the DTC
* The engine is running
* The system voltage is between 11-16 V
Conditions for Setting the DTC
P0461
* The ECM detects a difference between the fuel consumed by the engine and change of the fuel level signal of less than 1 L (0.26 gal) over a range of 30 L (7.92 gal) or 45.6% of the primary fuel tank.
* The above condition is present for about 300 seconds.
P0462
* The signal voltage is less than 0.25 V.
* The above conditions must be met for 5 seconds.
P0463
* The signal voltage is greater than 4.7 V.
* The above conditions must be met for 5 seconds.
P0464
* The fuel level change is greater than 10%.
* The above conditions must be met for 30 seconds.
* DTC P0464 runs and fails 2 out of 3 test cycles.
Action Taken When the DTC Sets
* P0461, P0462, P0463, and P0464 are Type B DTCs
* The fuel gauge defaults to empty
* The low fuel indicator illuminates
Conditions for Clearing the DTC
* P0461, P0462, P0463, and P0464 are Type B DTCs
* 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 Connector End Views By Name
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
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Programming and Relearning for scan tool information
Circuit/System Verification
1. Ignition ON, observe the scan tool ECM - Fuel Level Sensor parameter. The reading should be between 0.5-3.5 V and vary with fuel level.
2. Ignition ON, if no DTC's are set, perform the Instrument Cluster Gauge Sweep test with the scan tool, verify that the fuel level gauge sweeps from its low to high position
Note:
If any DTC's are set the fuel gauge will not sweep.
• If the fuel level gauge does not sweep, replace the P16 instrument cluster.
3. Command the All Indicators test ON and OFF with the scan tool, verify that the low fuel level indicator turns ON and OFF.
• If the low fuel level indicator always stays on or always off, replace the P16 instrument cluster.
• If no fuel or communication DTCs are set, the fuel level gauge does sweep, and the low fuel level indicator turns ON and OFF, replace the K20 ECM.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the A7 fuel pump and level sensor assembly.
2. Test for less than 30 ohms at the low reference circuit terminal 3.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
3. Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 4 and ground.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 ECM.
4. Remove the fuel level sensor.
5. Verify there is no damage to any component in the surrounding area of the fuel level sensor that would inhibit the mechanical range of the sensor.
• Repair or replace any damaged component as necessary.
6. If all circuits test normal, replace the A7 fuel pump and level sensor assembly.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Fuel Level Sensor Replacement
* Control Module References Programming and Relearning for the ECM replacement, programming and setup