WOMS
U code network Medium severity

U1587 U1587: "Module Communication Failure

The OBD2 code U1587 indicates a communication failure between modules in a vehicle's network, suggesting that one or more electronic control units (ECUs) are not communicating properly

Definition

The OBD2 code U1587 indicates a communication failure between modules in a vehicle's network, suggesting that one or more electronic control units (ECUs) are not communicating properly

Common causes

  • Faulty wiring or connectors
  • Failed or malfunctioning control module
  • Corrupted software or firmware in the module
  • Poor ground connections
  • Intermittent electrical issues
  • Communication network issues (e.g., CAN bus problems)
  • Low battery voltage or power supply issues
  • Damaged or corroded pins in connectors

Common misdiagnoses

  • Faulty wiring or connectors
  • Defective control module
  • Software issues or updates needed
  • Battery or power supply problems
  • Grounding issues
  • Intermittent communication issues
  • Other unrelated module failures

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other trouble codes that may be present. Other codes can provide context and help identify the root cause of the communication failure

  2. 2. Inspect Wiring and Connectors

    Visually inspect the wiring and connectors associated with the affected modules. Look for signs of damage, corrosion, loose connections, or broken wires

  3. 3. Pay special attention to ground connections, as poor grounding can lead to communication issues

  4. 4. Check Module Power Supply

    Ensure that the affected modules are receiving the proper voltage and ground. Use a multimeter to check the power supply to the modules

  5. 5. If a module is not receiving power, trace the wiring back to the fuse box and check for blown fuses or damaged wiring

  6. 6. Test the Affected Module

    If you suspect a specific module is causing the issue, you can test it by swapping it with a known good module (if available) or using a diagnostic tool to check its functionality

  7. 7. Some modules may have self-diagnostic capabilities that can provide additional information

  8. 8. Check for Software Updates

    Verify if there are any software updates available for the vehicle's modules. Sometimes, communication issues can be resolved with a software update from the manufacturer

  9. 9. Clear Codes and Test Drive

    After performing any repairs or inspections, clear the trouble codes using the OBD-II scanner and take the vehicle for a test drive to see if the code returns

  10. 10. Monitor the vehicle's performance and check for any symptoms that may indicate ongoing issues

  11. 11. Inspect the CAN Bus

    If the vehicle uses a Controller Area Network (CAN) bus, check for issues with the bus itself. Look for short circuits, open circuits, or interference that could disrupt communication between modules

  12. 12. Consult Technical Service Bulletins (TSBs)

    Check for any TSBs related to the U1587 code for your specific vehicle make and model. Manufacturers may have identified common issues and provided solutions

  13. 13. Professional Diagnosis

    If the issue persists after performing the above steps, consider seeking help from a professional mechanic or dealership. They may have specialized diagnostic tools and experience with your vehicle's specific systems. By following these troubleshooting steps, you can systematically identify and resolve the underlying issues causing the U1587 code