WOMS
U code network Medium severity

U1131 Lost Communication with Fuel Level Sensor

The OBD2 code U1131 indicates that there is a loss of communication between the vehicle's control module and the fuel level sensor, which may affect the accurate reading of the fuel level

Definition

The OBD2 code U1131 indicates that there is a loss of communication between the vehicle's control module and the fuel level sensor, which may affect the accurate reading of the fuel level

Common causes

  • Faulty fuel level sensor
  • Damaged wiring or connectors
  • Poor ground connection
  • Failed fuel pump module
  • Malfunctioning engine control module (ECM)
  • Corroded or loose electrical connections
  • Software issues or glitches in the vehicle's computer system

Common misdiagnoses

  • Faulty fuel level sensor
  • Wiring issues or shorts in the harness
  • Bad fuel gauge
  • Faulty engine control module (ECM)
  • Corroded connectors
  • Instrument cluster malfunction
  • Grounding issues
  • Fuel tank issues (e.g., damage or leaks)

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other trouble codes that may be present. This can provide more context and help identify related issues

  2. 2. Inspect the Fuel Level Sensor

    Location: Locate the fuel level sensor, which is typically found in the fuel tank

  3. 3. Visual Inspection

    Check for any visible damage to the sensor or its wiring. Look for frayed wires, corrosion, or loose connections

  4. 4. Check Electrical Connections

    Connector Inspection: Ensure that the electrical connectors to the fuel level sensor are secure and free of corrosion or dirt

  5. 5. Wiring

    Inspect the wiring harness for any signs of wear, damage, or shorts. Pay special attention to areas where the wiring may be exposed to heat or moving parts

  6. 6. Test the Fuel Level Sensor

    Resistance Test: Use a multimeter to measure the resistance of the fuel level sensor. Compare the readings to the specifications provided in the vehicle’s service manual

  7. 7. Functionality Test

    If possible, test the sensor by applying a known voltage and checking the output signal

  8. 8. Check the Fuel Pump Module

    In some vehicles, the fuel level sensor is part of the fuel pump module. Ensure that the entire module is functioning correctly

  9. 9. Inspect the Instrument Cluster

    If the fuel level sensor is functioning correctly, the issue may lie within the instrument cluster. Check for any faults in the cluster that could affect communication

  10. 10. Check for Ground Issues

    Ensure that the ground connections for the fuel level sensor and related components are secure and free of corrosion

  11. 11. Scan for Communication Issues

    Use a scan tool to check for communication between the fuel level sensor and the vehicle’s computer. Look for any communication errors that may indicate a problem with the CAN bus or other communication lines

  12. 12. Check for Software Updates

    Sometimes, manufacturers release software updates that can resolve communication issues. Check if there are any updates available for your vehicle’s ECU

  13. 13. Clear Codes and Test Drive

    After performing the above checks and repairs, clear the trouble codes using the OBD-II scanner and take the vehicle for a test drive to see if the code returns.1

  14. 14. Consult a Professional

    If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician who has access to specialized diagnostic equipment. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the U1131 code. Always refer to the specific service manual for your vehicle for detailed procedures and specifications