WOMS
U code network Medium severity

U1724 U1724: Transmission Control Module Communication Error

The OBD2 code U1724 indicates a communication error between the Transmission Control Module (TCM) and other control modules in the vehicle, suggesting a potential issue with data transmission or connectivity

Definition

The OBD2 code U1724 indicates a communication error between the Transmission Control Module (TCM) and other control modules in the vehicle, suggesting a potential issue with data transmission or connectivity

Common causes

  • Faulty Transmission Control Module (TCM)
  • Damaged wiring or connectors
  • Poor ground connections
  • Corroded terminals
  • Faulty Engine Control Module (ECM)
  • Software issues or updates needed
  • Electrical interference
  • Low battery voltage or weak battery
  • Faulty CAN bus communication
  • Malfunctioning sensors related to transmission

Common misdiagnoses

  • Faulty Transmission Control Module (TCM)
  • Wiring issues or damaged connectors
  • Faulty Engine Control Module (ECM)
  • Low transmission fluid levels
  • Faulty sensors (e.g., speed sensors)
  • Software issues or programming errors
  • Battery or charging system problems
  • Grounding issues
  • Faulty transmission solenoids
  • Corroded or loose electrical connections

Troubleshooting steps

  1. 1. Check for Other Codes

    Use an OBD-II scanner to check for any additional trouble codes. Sometimes, related codes can provide more context for the issue

  2. 2. Inspect Wiring and Connectors

  3. 3. Visually inspect the wiring harness and connectors associated with the TCM. Look for signs of damage, corrosion, or loose connections

  4. 4. Ensure that all connectors are securely plugged in and that there are no bent pins

  5. 5. Check Power and Ground

  6. 6. Verify that the TCM is receiving the correct power supply. Use a multimeter to check the voltage at the TCM connector

  7. 7. Check the ground connections to ensure they are secure and free of corrosion

  8. 8. Inspect the CAN Bus

  9. 9. The TCM communicates with other modules via the Controller Area Network (CAN) bus. Inspect the CAN bus wiring for damage or shorts

  10. 10. Use a scan tool to monitor the CAN bus for any irregularities in communication

  11. 11. Test the TCM

  12. 12. If the wiring and connections are intact, the TCM itself may be faulty. If possible, test the TCM in another vehicle or replace it with a known good unit to see if the problem persists

  13. 13. Check for Software Updates

  14. 14. Sometimes, a software update for the TCM or other control modules can resolve communication issues. Check with the manufacturer for any available updates

  15. 15. Clear Codes and Test Drive

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

  17. 17. Refer to the vehicle's service manual for specific diagnostic procedures related to the TCM and communication errors. This can provide additional insights and steps tailored to your vehicle

  18. 18. Professional Diagnosis

  19. 19. If the issue persists after performing the above steps, consider seeking help from a professional mechanic or dealership. They may have specialized tools and knowledge to diagnose complex communication issues. By following these steps, you can systematically identify and resolve the underlying cause of the U1724 code