WOMS
C code chassis High severity

C0290 Lost Communications With PCM

The OBD2 code C0290 indicates a loss of communication between the vehicle's control module and the Powertrain Control Module (PCM), which can affect engine performance and diagnostics

Definition

The OBD2 code C0290 indicates a loss of communication between the vehicle's control module and the Powertrain Control Module (PCM), which can affect engine performance and diagnostics

Common causes

  • Faulty PCM (Powertrain Control Module)
  • Wiring issues or damaged connectors
  • Corroded terminals
  • Faulty communication lines (CAN bus)
  • Blown fuses
  • Battery or power supply issues
  • Grounding problems
  • Software or firmware issues in the PCM
  • Interference from aftermarket devices or modifications

Common misdiagnoses

  • Faulty PCM (Powertrain Control Module)
  • Wiring issues or damaged connectors
  • Faulty sensors (e.g., crankshaft or camshaft position sensors)
  • Battery or charging system problems
  • Grounding issues
  • Faulty transmission control module
  • Issues with the vehicle's electrical system
  • Corrupted software or firmware in the PCM

Troubleshooting steps

  1. 1. Check for Other Codes

    Use an OBD-II scanner to check for any additional trouble codes. Other codes may provide more context or indicate related issues

  2. 2. Inspect Wiring and Connectors

  3. 3. Visually inspect the wiring harness and connectors related to the PCM for any signs of damage, corrosion, or loose connections

  4. 4. Pay special attention to the connectors at the PCM and any related modules

  5. 5. Check Power and Ground

  6. 6. Ensure that the PCM is receiving proper power and ground. Use a multimeter to check the voltage at the PCM connector

  7. 7. Verify that the ground connections are secure and free of corrosion

  8. 8. Test the PCM

  9. 9. If possible, test the PCM with a known good unit to determine if the PCM itself is faulty

  10. 10. Some vehicles may require specific procedures to reprogram or reset the PCM after replacement

  11. 11. Inspect Other Modules

  12. 12. Check for communication issues with other modules in the vehicle. If other modules are not communicating properly, it may affect the PCM's ability to communicate

  13. 13. Use a scan tool to check the status of other modules and ensure they are functioning correctly

  14. 14. Check for Short Circuits

  15. 15. Look for any short circuits in the wiring that could be causing communication issues. This may require a more in-depth inspection of the wiring harness

  16. 16. Look for Software Updates

  17. 17. Check if there are any software updates available for the PCM or other modules. Sometimes, manufacturers release updates to fix communication issues

  18. 18. Inspect for Environmental Factors

  19. 19. Ensure that there are no environmental factors affecting the PCM, such as moisture or extreme temperatures

  20. 20. Clear Codes and Test Drive

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

  22. 22. Refer to the vehicle's service manual for specific diagnostic procedures and wiring diagrams related to the PCM and communication systems. If the issue persists after following these steps, it may be necessary to consult a professional mechanic or technician who has experience with the specific make and model of the vehicle