WOMS
U code network High severity

U2119 Lost Communication with the Transmission Control Module (TCM)

The OBD2 code U2119 indicates that there is a communication failure between the vehicle's Engine Control Module (ECM) and the Transmission Control Module (TCM), meaning the ECM is unable to receive data from the TCM

Definition

The OBD2 code U2119 indicates that there is a communication failure between the vehicle's Engine Control Module (ECM) and the Transmission Control Module (TCM), meaning the ECM is unable to receive data from the TCM

Common causes

  • Faulty Transmission Control Module (TCM)
  • Damaged wiring or connectors
  • Poor electrical connections
  • Failed or malfunctioning engine control module (ECM)
  • Blown fuses
  • Corroded terminals
  • Software issues or updates needed
  • Low battery voltage or weak battery
  • Faulty transmission wiring harness
  • Issues with the vehicle's CAN bus system

Common misdiagnoses

  • Faulty Transmission Control Module (TCM)
  • Wiring issues or damaged connectors
  • Faulty Engine Control Module (ECM)
  • Low transmission fluid levels
  • Faulty vehicle speed sensor
  • Corrupted software or firmware in TCM or ECM
  • Issues with the CAN bus communication system
  • Faulty or damaged transmission solenoids
  • Battery or charging system problems
  • Grounding issues in the electrical system

Troubleshooting steps

  1. 1. Check for Other Codes

    Use an OBD-II scanner to check for any additional trouble codes. Codes related to the TCM or transmission may provide more context for the issue

  2. 2. Inspect Wiring and Connectors

    Visual Inspection: Check the wiring harness and connectors leading to the TCM 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. Check Power and Ground

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

  5. 5. Ground Connections

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

  6. 6. Inspect the TCM

    Physical Condition: Check the TCM for any signs of physical damage or water intrusion

  7. 7. Reprogramming

    If applicable, consider reprogramming or updating the TCM software, as a software glitch can sometimes cause communication issues

  8. 8. Scan Tool Communication

    Communication Check: Use a scan tool to check if you can communicate with the TCM. If you cannot, it may indicate a problem with the TCM itself or the communication lines

  9. 9. Other Modules

    Check if you can communicate with other modules in the vehicle. If other modules are also unresponsive, it may indicate a broader communication issue

  10. 10. Check for Bus Communication Issues

    CAN Bus Inspection: If your vehicle uses a CAN bus system, check for issues on the bus. Look for short circuits, open circuits, or other faults that could disrupt communication

  11. 11. Termination Resistors

    Ensure that the CAN bus termination resistors are present and functioning correctly

  12. 12. Test the TCM

    If all other checks are satisfactory, consider testing the TCM itself. This may involve swapping it with a known good unit if available

  13. 13. Check for Environmental Factors

    Temperature: Extreme temperatures can affect electronic components. Ensure that the TCM is not exposed to conditions that could cause it to fail

  14. 14. Consult Technical Service Bulletins (TSBs)

    Check for any TSBs related to your vehicle make and model that may address known issues with the TCM or communication problems

  15. 15. Professional Diagnosis

    If you are unable to resolve the issue after these steps, it may be best to consult a professional mechanic or technician who has experience with your specific vehicle make and model.Conclusion Troubleshooting a U2119 code involves a systematic approach to check for communication issues between the TCM and other vehicle systems. By following these steps, you can identify the root cause of the problem and take appropriate action to resolve it