WOMS
U code network High severity

U2091 Lost Communication with the Fuel Pump Control Module

The OBD2 code U2091 indicates a loss of communication between the vehicle's control module and the fuel pump control module, suggesting a potential issue with wiring, connectors, or the fuel pump control module itself

Definition

The OBD2 code U2091 indicates a loss of communication between the vehicle's control module and the fuel pump control module, suggesting a potential issue with wiring, connectors, or the fuel pump control module itself

Common causes

  • Faulty Fuel Pump Control Module
  • Damaged wiring or connectors
  • Poor ground connection
  • Blown fuse
  • Faulty Engine Control Module (ECM)
  • Corroded terminals
  • Intermittent electrical issues
  • Software issues or updates needed
  • Fuel pump failure

Common misdiagnoses

  • Faulty fuel pump
  • Bad fuel pump relay
  • Wiring issues or shorts
  • Defective Engine Control Module (ECM)
  • Faulty fuel level sensor
  • Bad ground connections
  • Issues with the powertrain control module (PCM)
  • Corroded connectors or terminals

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 Wiring and Connectors

    Visual Inspection: Check the wiring harness and connectors related to the fuel pump control module for any signs of damage, corrosion, or loose connections

  3. 3. Connector Pins

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

  4. 4. Test the Fuel Pump Control Module

    Power and Ground: Verify that the fuel pump control module is receiving the correct power and ground signals. Use a multimeter to check voltage and ground continuity

  5. 5. Module Functionality

    If possible, test the fuel pump control module separately to ensure it is functioning correctly

  6. 6. Check for Communication Issues

    CAN Bus Communication: Since U2091 is a communication-related code, check the CAN bus for proper operation. Look for any shorts, opens, or faults in the communication lines

  7. 7. Scan Tool Communication

    Ensure that your scan tool can communicate with the fuel pump control module. If it cannot, there may be a communication issue

  8. 8. Inspect the Fuel Pump

    Operation Check: Ensure that the fuel pump is functioning correctly. You can do this by listening for the pump operation when the ignition is turned on or by checking fuel pressure

  9. 9. Power Supply

    Verify that the fuel pump is receiving power when commanded by the control module

  10. 10. Check for Ground Issues

    Ensure that all ground connections related to the fuel pump control module and the fuel pump itself are secure and free of corrosion

  11. 11. Look for Environmental Factors

    Check for any environmental factors that may affect the fuel pump control module, such as moisture or heat that could cause intermittent failures

  12. 12. Perform a Reset

    After addressing any issues found, clear the trouble codes using the OBD-II scanner and take the vehicle for a test drive to see if the code returns

  13. 13. Consult Technical Service Bulletins (TSBs)

    Check for any manufacturer-specific TSBs related to the fuel pump control module or communication issues that may provide additional guidance

  14. 14. Seek Professional Help

    If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician who has experience with your specific vehicle make and model. By following these troubleshooting steps, you should be able to identify the root cause of the U2091 code and take appropriate action to resolve the issue