WOMS
U code network High severity

U1980 Lost Communication with the Body Control Module (BCM)

The OBD2 code U1980 indicates a loss of communication between the vehicle's control module and the Body Control Module (BCM), which may affect various electrical systems and functions

Definition

The OBD2 code U1980 indicates a loss of communication between the vehicle's control module and the Body Control Module (BCM), which may affect various electrical systems and functions

Common causes

  • Faulty Body Control Module (BCM)
  • Damaged wiring or connectors
  • Corroded terminals
  • Blown fuses
  • Faulty communication network (CAN bus issues)
  • Low battery voltage
  • Intermittent electrical connections
  • Software issues or programming errors

Common misdiagnoses

  • Faulty Body Control Module (BCM)
  • Wiring issues or damaged connectors
  • Faulty or corroded ground connections
  • Issues with the power supply to the BCM
  • Faulty ignition switch
  • Problems with other control modules
  • Software or programming issues
  • Faulty sensors or actuators related to the BCM

Troubleshooting steps

  1. 1. Check for Other Codes

    Use an OBD-II scanner to check for any additional trouble codes. Sometimes, other codes can provide context or indicate related issues

  2. 2. Inspect the Wiring and Connectors

    Visual Inspection: Check the wiring harness and connectors leading to the BCM 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 pushed back

  4. 4. Check Power and Ground

    Power Supply: Verify that the BCM is receiving the correct voltage. Use a multimeter to check the power supply at the BCM connector

  5. 5. Ground Connections

    Ensure that the ground connections for the BCM are secure and free of corrosion

  6. 6. Inspect Fuses

    Check the vehicle’s fuse box for any blown fuses related to the BCM or other modules. Replace any blown fuses and retest

  7. 7. Test the BCM

    If possible, perform a functional test of the BCM. This may require specialized diagnostic equipment or software

  8. 8. If you have access to a known good BCM, you can swap it out to see if the issue persists

  9. 9. Check for Communication Issues

    Use a scan tool to check if other modules in the vehicle can communicate with the BCM. If other modules are also having communication issues, it may indicate a network problem

  10. 10. Inspect the CAN (Controller Area Network) bus wiring for shorts, opens, or other issues

  11. 11. Look for Environmental Factors

    Check for moisture or water intrusion in the BCM area, which can cause communication issues

  12. 12. Ensure that there are no aftermarket accessories or modifications that could interfere with the BCM’s operation

  13. 13. Reset the System

    Clear the trouble codes using the OBD-II scanner and see if the code returns after a test drive. Sometimes, a reset can resolve temporary communication issues

  14. 14. Consult Technical Service Bulletins (TSBs)

    Check for any TSBs related to the BCM or communication issues for your specific vehicle make and model. Manufacturers may have issued guidance on common problems

  15. 15. Seek Professional Help

    If the issue persists after performing the above steps, it may be necessary to consult a professional mechanic or dealership for further diagnosis. They may have access to advanced diagnostic tools and resources.Conclusion Troubleshooting a U1980 code can be complex, as it may involve multiple systems and components. Following these steps systematically can help identify the root cause of the communication issue with the BCM