WOMS
U code network Medium severity

U1679 Invalid Data Received from Vehicle Control Module

The OBD2 code U1679 indicates that the vehicle's control module has received invalid or corrupted data from another control module, which may affect vehicle performance or functionality

Definition

The OBD2 code U1679 indicates that the vehicle's control module has received invalid or corrupted data from another control module, which may affect vehicle performance or functionality

Common causes

  • Faulty Vehicle Control Module (VCM)
  • Poor or damaged wiring/connectors
  • Corrupted software or firmware in the VCM
  • Communication issues between modules
  • Low battery voltage or electrical issues
  • Faulty sensors sending incorrect data
  • Interference from aftermarket devices or modifications

Common misdiagnoses

  • Faulty Vehicle Control Module (VCM)
  • Wiring issues or shorts in the communication lines
  • Faulty sensors or actuators
  • Corrupted software or firmware in the VCM
  • Issues with the power supply to the VCM
  • Problems with other control modules in the vehicle
  • Incorrectly installed aftermarket accessories or modifications

Troubleshooting steps

  1. 1. Check for Other Codes

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

  2. 2. Inspect Wiring and Connectors

  3. 3. Visually inspect the wiring and connectors related to the VCM and any other modules involved in the communication network

  4. 4. Look for signs of damage, corrosion, or loose connections

  5. 5. Repair or replace any damaged wiring or connectors

  6. 6. Check for Communication Issues

  7. 7. Ensure that the communication lines (CAN bus) are functioning properly. Use a multimeter to check for continuity and proper voltage levels

  8. 8. If you have access to a scan tool that can monitor live data, check if the VCM is communicating with other modules

  9. 9. Inspect the Control Modules

  10. 10. If the wiring and connections are good, the issue may lie within the control modules themselves. Check for any signs of physical damage or water intrusion

  11. 11. If possible, perform a software update on the VCM and other related modules, as outdated software can sometimes cause communication issues

  12. 12. Reset the Codes

  13. 13. 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

  14. 14. Check Battery and Ground Connections

  15. 15. Ensure that the vehicle's battery is in good condition and that all ground connections are secure. Poor power supply or grounding can lead to communication errors

  16. 16. Consult Technical Service Bulletins (TSBs)

  17. 17. Check for any TSBs related to the U1679 code for your specific vehicle make and model. Manufacturers may have specific recommendations or known issues that can help in diagnosing the problem

  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 diagnostic tools and experience with your vehicle's specific systems. By following these steps, you should be able to identify and resolve the underlying issue causing the U1679 code