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U code network High severity

U1597 Lost Communication with the Fuel Pump Control Module

The OBD2 code U1597 indicates a loss of communication between the vehicle's control module and the fuel pump control module, which may affect the fuel pump's operation

Definition

The OBD2 code U1597 indicates a loss of communication between the vehicle's control module and the fuel pump control module, which may affect the fuel pump's operation

Common causes

  • Faulty Fuel Pump Control Module
  • Wiring issues (damaged, corroded, or loose connections)
  • Faulty fuel pump
  • Blown fuse
  • Malfunctioning engine control module (ECM)
  • Poor ground connection
  • Communication network issues (CAN bus problems)
  • Software glitches or updates needed in the control modules

Common misdiagnoses

  • Faulty fuel pump
  • Bad fuel pump relay
  • Wiring issues or shorts in the harness
  • Defective engine control module (ECM)
  • Faulty fuel level sensor
  • Bad ground connections
  • Issues with the ignition switch
  • Corrupted software in the fuel pump control module

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 by substituting it with a known good unit to see if the issue persists

  6. 6. Check for Communication Issues

    CAN Bus Integrity: Inspect the CAN bus wiring for shorts, opens, or other issues that could affect communication between modules

  7. 7. Scan Tool Communication

    Use a scan tool to check if you can communicate with the fuel pump control module. If you cannot, it may indicate a problem with the module or the communication lines

  8. 8. Inspect the Fuel Pump

    Fuel Pump Operation: 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 testing the pump directly

  9. 9. Fuel Pump Relay

    Check the fuel pump relay for proper operation. A faulty relay can prevent the fuel pump from receiving power

  10. 10. Check for Ground Issues

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

  11. 11. Look for Environmental Factors

    Check for any environmental factors that could affect the fuel pump control module, such as moisture or exposure to extreme temperatures

  12. 12. Perform a System 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. There may be known fixes or recalls

  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 U1597 code and take appropriate action to resolve the issue