WOMS
P code powertrain Medium severity

P1690 Wastegate Solenoid Circuit Malfunction

The OBD2 code P1690 indicates a malfunction in the wastegate solenoid circuit, which can affect the turbocharger's ability to regulate boost pressure properly

Definition

The OBD2 code P1690 indicates a malfunction in the wastegate solenoid circuit, which can affect the turbocharger's ability to regulate boost pressure properly

Common causes

  • Faulty wastegate solenoid
  • Damaged wiring or connectors
  • Short circuit in the solenoid circuit
  • Open circuit in the solenoid circuit
  • Failed engine control module (ECM)
  • Vacuum leaks
  • Faulty turbocharger wastegate actuator

Common misdiagnoses

  • Turbocharger failure
  • Boost pressure sensor malfunction
  • Engine control module (ECM) issues
  • Wiring or connector problems
  • Vacuum leaks
  • Faulty wastegate actuator
  • Fuel system issues
  • Ignition system problems
  • Exhaust system restrictions
  • Other solenoid malfunctions

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 the Wiring and Connectors

    Visually inspect the wiring and connectors associated with the wastegate solenoid. Look for signs of damage, corrosion, or loose connections

  3. 3. Ensure that the connectors are securely attached and that there are no broken wires

  4. 4. Test the Wastegate Solenoid

    Disconnect the wastegate solenoid and test it with a multimeter to check for proper resistance. Refer to the vehicle’s service manual for the specific resistance values

  5. 5. If the solenoid is not within the specified range, it may need to be replaced

  6. 6. Check the Power and Ground Supply

    With the ignition on (engine off), use a multimeter to check for voltage at the wastegate solenoid connector. You should see battery voltage

  7. 7. Also, check for a good ground connection. If there is no power or ground, trace the wiring back to the engine control module (ECM) to find the issue

  8. 8. Inspect the Vacuum Lines (if applicable)

    If the wastegate is vacuum-operated, check the vacuum lines for leaks, cracks, or disconnections. A vacuum leak can cause the wastegate to malfunction

  9. 9. Check the Turbocharger and Wastegate Operation

    Ensure that the turbocharger and wastegate are functioning properly. Manually operate the wastegate (if possible) to see if it moves freely

  10. 10. Look for any signs of damage or excessive wear on the turbocharger components

  11. 11. Examine the Engine Control Module (ECM)

    If all other components check out, there may be an issue with the ECM itself. Check for software updates or reprogramming if necessary

  12. 12. In some cases, the ECM may need to be replaced, but this is usually a last resort after all other possibilities have been exhausted

  13. 13. Clear the Codes and Test Drive

    After performing repairs or replacements, clear the trouble codes using the OBD-II scanner

  14. 14. Take the vehicle for a test drive to see if the code returns. Monitor the vehicle’s performance to ensure the issue is resolved

  15. 15. Consult a Professional

    If you are unable to diagnose or fix the issue, it may be best to consult a professional mechanic who has experience with your specific vehicle make and model. By following these steps, you should be able to identify and resolve the issue related to the P1690 code. Always refer to the vehicle's service manual for specific details and specifications related to your vehicle