WOMS
U code network High severity

U1375 Invalid Data Received from the Transmission Control Module (TCM)

The OBD2 code U1375 indicates that the Engine Control Module (ECM) has received invalid or corrupted data from the Transmission Control Module (TCM), which may affect vehicle performance and transmission operation

Definition

The OBD2 code U1375 indicates that the Engine Control Module (ECM) has received invalid or corrupted data from the Transmission Control Module (TCM), which may affect vehicle performance and transmission operation

Common causes

  • Faulty Transmission Control Module (TCM)
  • Poor electrical connections or wiring issues
  • Corrupted data communication between TCM and other modules
  • Software or firmware issues in the TCM
  • Faulty sensors related to transmission operation
  • Low transmission fluid levels or quality
  • Malfunctioning engine control module (ECM)
  • Grounding issues in the vehicle's electrical system

Common misdiagnoses

  • Faulty Transmission Control Module (TCM)
  • Wiring issues or short circuits in the transmission harness
  • Faulty Engine Control Module (ECM)
  • Incorrectly calibrated or faulty sensors (e.g., speed sensors)
  • Transmission fluid issues (low fluid, contamination)
  • Faulty or damaged connectors
  • Software or firmware issues in the TCM or ECM
  • Mechanical transmission problems (e.g., slipping, internal damage)

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other trouble codes that may be present. This can provide more context and help identify related issues

  2. 2. Inspect Wiring and Connectors

    Visual Inspection: Check the wiring harness and connectors between the ECM and TCM for any signs of damage, corrosion, or loose connections

  3. 3. Repair or Replace

    If any issues are found, repair or replace the damaged wiring or connectors

  4. 4. Check for Software Updates

    Manufacturer Updates: Check if there are any software updates available for the ECM or TCM from the vehicle manufacturer. Sometimes, software bugs can cause communication issues

  5. 5. Test the TCM

    Functionality Check: Use a scan tool to check the TCM for any internal faults or issues. If the TCM is malfunctioning, it may need to be repaired or replaced

  6. 6. Communication Test

    Verify that the TCM is communicating properly with the ECM. This can often be done with a professional scan tool

  7. 7. Inspect Ground Connections

    Ensure that all ground connections related to the ECM and TCM are secure and free of corrosion. Poor ground connections can lead to communication issues

  8. 8. Check Power Supply

    Verify that the TCM is receiving the correct voltage and ground. Use a multimeter to check the power supply to the TCM

  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. Consult Technical Service Bulletins (TSBs)

    Check for any TSBs related to the U1375 code for your specific vehicle make and model. Manufacturers may have specific recommendations or known issues

  11. 11. Professional Diagnosis

    If the issue persists after performing the above steps, consider seeking help from a professional mechanic or dealership. They may have access to specialized diagnostic tools and knowledge of specific vehicle issues

  12. 12. Replace the TCM (if necessary)

    If all other troubleshooting steps fail and the TCM is determined to be faulty, it may need to be replaced. Ensure that the replacement TCM is compatible with your vehicle. By following these steps, you should be able to identify and resolve the issue causing the U1375 code. Always refer to the vehicle's service manual for specific procedures and specifications