WOMS
U code network High severity

U0139 Lost Communication With Suspension Control Module "B

The OBD2 code U0139 indicates a loss of communication with the Suspension Control Module "B," which may affect the vehicle's suspension system performance

Definition

The OBD2 code U0139 indicates a loss of communication with the Suspension Control Module "B," which may affect the vehicle's suspension system performance

Common causes

  • Faulty Suspension Control Module
  • Damaged wiring or connectors
  • Corroded connectors
  • Poor ground connection
  • Faulty CAN bus communication
  • Blown fuse
  • Software issues or glitches
  • Battery voltage issues

Common misdiagnoses

  • Faulty Suspension Control Module
  • Wiring Issues or Short Circuits
  • Faulty Body Control Module
  • Faulty ABS Module
  • Corroded Connectors or Pins
  • Battery or Charging System Problems
  • Faulty Wheel Speed Sensors
  • Software or Calibration Issues

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other related trouble codes. This can provide more context and help identify if there are other issues affecting the suspension control module

  2. 2. Inspect Wiring and Connectors

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

  4. 4. Check Power and Ground

    Power Supply: Verify that the suspension control module is receiving the correct voltage. Use a multimeter to check the power supply at the module

  5. 5. Ground Connection

    Ensure that the ground connection for the module is secure and functioning properly

  6. 6. Inspect the Suspension Control Module

    If the wiring and connections are intact, the suspension control module itself may be faulty. Check for any signs of physical damage or water intrusion

  7. 7. If possible, test the module by swapping it with a known good unit (if available)

  8. 8. Check for Communication Issues

    CAN Bus Communication: Since the suspension control module communicates over the CAN bus, check for issues with the CAN bus wiring or other modules on the bus that may be causing communication problems

  9. 9. Network Integrity

    Use a scan tool to monitor the CAN bus for any irregularities or communication failures with other modules

  10. 10. Perform a Module Reset

    Sometimes, resetting the module can clear temporary communication issues. Disconnect the battery for a few minutes, then reconnect it and see if the code returns

  11. 11. Software Updates

    Check if there are any software updates available for the vehicle’s control modules. Sometimes, manufacturers release updates to fix known communication issues

  12. 12. Consult Technical Service Bulletins (TSBs)

    Look for any TSBs related to the suspension control module or communication issues for your specific vehicle make and model. Manufacturers may have documented solutions for known problems

  13. 13. Professional Diagnosis

    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 specialized tools and knowledge to address complex issues.Conclusion By following these troubleshooting steps, you can systematically identify and resolve the issue related to the U0139 code. Always ensure safety precautions are taken when working on a vehicle's electrical system