WOMS
U code network Medium severity

U1137 Lost Communication with Fuel Level Sensor 'A'

The OBD2 code U1137 indicates that there is a communication failure between the vehicle's control module and the fuel level sensor 'A', which may affect the accurate reading of the fuel level

Definition

The OBD2 code U1137 indicates that there is a communication failure between the vehicle's control module and the fuel level sensor 'A', which may affect the accurate reading of the fuel level

Common causes

  • Faulty fuel level sensor
  • Damaged wiring or connectors
  • Poor ground connection
  • Failed engine control module (ECM)
  • Corroded or loose electrical connections
  • Short circuit in the wiring harness
  • Intermittent signal loss
  • Faulty fuel gauge or instrument cluster
  • Software issues in the ECM

Common misdiagnoses

  • Faulty fuel level sensor
  • Wiring issues or damaged connectors
  • Faulty engine control module (ECM)
  • Incorrectly calibrated fuel gauge
  • Fuel tank issues (e.g., float malfunction)
  • Faulty body control module (BCM)
  • Software glitches in the vehicle's computer system

Troubleshooting steps

  1. 1. Check for Additional Codes

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

  2. 2. Inspect the Wiring and Connectors

    Visual Inspection: Check the wiring harness and connectors associated with the fuel level sensor for any signs of damage, corrosion, or loose connections

  3. 3. Connector Pins

    Ensure that the pins in the connectors are not bent or corroded

  4. 4. Test the Fuel Level Sensor

    Resistance Check: 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

  5. 5. Functionality Test

    If possible, test the sensor by applying a known voltage and checking if the output changes accordingly

  6. 6. Check the Fuel Level Sensor Circuit

    Continuity Test: Perform a continuity test on the wiring between the fuel level sensor and the engine control module (ECM) to ensure there are no breaks in the circuit

  7. 7. Voltage Check

    Check for proper voltage supply to the fuel level sensor. Ensure that the sensor is receiving the correct voltage as specified in the service manual

  8. 8. Inspect the ECM

    Connections: Check the connections at the ECM for any signs of damage or corrosion

  9. 9. Software Update

    In some cases, a software update for the ECM may be necessary. Check with the manufacturer for any available updates

  10. 10. Check for Ground Issues

    Ensure that the fuel level sensor has a good ground connection. A poor ground can lead to communication issues

  11. 11. Scan for Communication Issues

    Use a scan tool to check for communication between the ECM and the fuel level sensor. If there are communication errors, it may indicate a problem with the bus system

  12. 12. Inspect Other Related Components

    Check other components that may affect the fuel level sensor, such as the fuel pump module or any related sensors

  13. 13. Clear Codes and Test Drive

    After performing the above checks and repairs, clear the trouble codes and take the vehicle for a test drive to see if the code returns

  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 advanced diagnostic tools and equipment. By following these troubleshooting steps, you should be able to identify the cause of the U1137 code and take appropriate action to resolve the issue