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P code powertrain High severity

P012D Turbocharger/Supercharger Inlet Pressure Sensor Circuit High (Downstream of throttle valve)

The OBD2 code P012D indicates that the turbocharger or supercharger inlet pressure sensor circuit is reading a high voltage or signal, which suggests a potential issue with the sensor or its wiring, specifically...

Definition

The OBD2 code P012D indicates that the turbocharger or supercharger inlet pressure sensor circuit is reading a high voltage or signal, which suggests a potential issue with the sensor or its wiring, specifically downstream of the throttle valve

Common causes

  • Faulty turbocharger/supercharger inlet pressure sensor
  • Damaged wiring or connectors in the sensor circuit
  • Short circuit in the sensor circuit
  • Open circuit in the sensor circuit
  • Vacuum leaks in the intake system
  • Faulty engine control module (ECM)
  • Blocked or restricted intake passages
  • Incorrectly installed or malfunctioning throttle body

Common misdiagnoses

  • Faulty throttle position sensor
  • Vacuum leaks
  • Mass air flow sensor issues
  • Boost pressure sensor problems
  • Turbocharger or supercharger malfunctions
  • Wiring or connector issues
  • Engine control module (ECM) faults
  • Intake air temperature sensor faults
  • Fuel delivery problems
  • Exhaust gas recirculation (EGR) system issues

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other related trouble codes. This can provide more context and help identify if there are multiple issues

  2. 2. Inspect the Wiring and Connectors

    Visual Inspection: Look for damaged, frayed, or corroded wires and connectors related to the inlet pressure sensor

  3. 3. Connector Condition

    Ensure that the connectors are securely attached and free of moisture or dirt

  4. 4. Test the Inlet Pressure Sensor

    Sensor Functionality: Use a multimeter to check the resistance and voltage output of the inlet pressure sensor. Compare the readings to the manufacturer’s specifications

  5. 5. Sensor Ground

    Ensure that the sensor has a good ground connection

  6. 6. Check for Vacuum Leaks

    Inspect the intake system for any vacuum leaks that could affect the pressure readings. This includes checking hoses, gaskets, and the throttle body

  7. 7. Inspect the Throttle Body

    Ensure that the throttle body is clean and functioning properly. A malfunctioning throttle body can affect pressure readings

  8. 8. Check the Engine Control Module (ECM)

    Ensure that the ECM is functioning correctly. Sometimes, a software update or reprogramming may be necessary

  9. 9. Test the Circuit

    Use a multimeter to check the voltage and ground at the sensor connector while the engine is running. Compare these readings to the specifications in the service manual

  10. 10. Check for Intermittent Issues

    If the code is intermittent, monitor the vehicle’s performance and check for conditions that may trigger the code, such as temperature changes or specific driving conditions

  11. 11. Clear the Code and Test Drive

    After performing the checks and repairs, clear the code and take the vehicle for a test drive to see if the code returns

  12. 12. Consult Technical Service Bulletins (TSBs)

    Check for any TSBs related to the P012D code for your specific vehicle make and model, as there may be known issues or fixes.1

  13. 13. Professional Diagnosis

    If the issue persists after performing the above steps, consider seeking help from a professional mechanic or technician who has access to advanced diagnostic tools. By following these steps, you should be able to identify and resolve the issue related to the P012D code. Always refer to the vehicle’s service manual for specific procedures and specifications