WOMS
U code network High severity

U013A Lost Communication with Body Control Module (BCM) 'A'

The OBD2 code U013A indicates that there is a loss of communication with the Body Control Module (BCM) 'A', which may affect various electrical systems in the vehicle

Definition

The OBD2 code U013A indicates that there is a loss of communication with the Body Control Module (BCM) 'A', which may affect various electrical systems in the vehicle

Common causes

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

Common misdiagnoses

  • Faulty Body Control Module (BCM)
  • Wiring issues or shorts in the communication circuit
  • Faulty or corroded connectors
  • Issues with other control modules
  • Battery or power supply problems
  • Faulty ignition switch
  • Software or programming issues
  • Grounding problems

Troubleshooting steps

  1. 1. Check for Other Codes

    Use an OBD-II scanner to check for any additional trouble codes. Other codes may provide more context or indicate related issues

  2. 2. Inspect Wiring and Connectors

    Visual Inspection: Check the wiring harness and connectors related 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 to the module

  5. 5. Ground Connections

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

  6. 6. Test the Body Control Module

    If possible, test the BCM itself. This may involve using a scan tool to check for communication with the module or replacing it with a known good unit to see if the problem persists

  7. 7. Inspect Related Modules

    Check for communication issues with other modules in the vehicle. If other modules are also reporting communication errors, it may indicate a broader network issue

  8. 8. Check for Short Circuits or Open Circuits

    Use a multimeter to check for shorts to ground or open circuits in the wiring that connects to the BCM

  9. 9. Look for Software Issues

    Sometimes, a software update may be required for the BCM or other modules. Check with the manufacturer for any available updates

  10. 10. Clear Codes and Test Drive

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

  11. 11. Consult Technical Service Bulletins (TSBs)

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

  12. 12. 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.Additional Tips: - Always ensure that the vehicle's battery is in good condition, as low voltage can cause communication issues. - Be cautious when working with electrical components; disconnect the battery before performing any repairs to avoid shorts or damage. By following these steps, you should be able to identify the cause of the U013A code and take appropriate action to resolve the issue