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P231B Ignition Coil 'D' Secondary Circuit High

The OBD2 code P231B indicates a problem with the ignition coil 'D' secondary circuit, specifically that the circuit is experiencing a high voltage condition

Definition

The OBD2 code P231B indicates a problem with the ignition coil 'D' secondary circuit, specifically that the circuit is experiencing a high voltage condition

Common causes

  • Faulty ignition coil 'D'
  • Open or shorted wiring in the ignition coil circuit
  • Poor electrical connections or corroded terminals
  • Faulty engine control module (ECM)
  • High resistance in the ignition coil circuit
  • Faulty spark plugs or spark plug wires
  • Issues with the power supply to the ignition coil

Common misdiagnoses

  • Faulty ignition coil
  • Bad spark plugs
  • Wiring issues or shorts
  • Faulty engine control module (ECM)
  • Fuel delivery problems
  • Vacuum leaks
  • Incorrectly installed ignition components
  • Faulty crankshaft or camshaft position sensors

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 Ignition Coil

  3. 3. Visually inspect the ignition coil 'D' for any signs of damage, such as cracks, corrosion, or burnt areas

  4. 4. Ensure that the electrical connectors are secure and free of corrosion

  5. 5. Test the Ignition Coil

  6. 6. Use a multimeter to test the resistance of the ignition coil. Compare the readings to the specifications provided in the vehicle's service manual

  7. 7. If the resistance is outside the specified range, the ignition coil may be faulty and should be replaced

  8. 8. Check Wiring and Connectors

  9. 9. Inspect the wiring harness and connectors leading to the ignition coil for any signs of wear, fraying, or damage

  10. 10. Look for loose connections or broken wires that could cause a poor electrical connection

  11. 11. Test the Power and Ground

  12. 12. Use a multimeter to check for proper voltage at the ignition coil connector. You should see battery voltage when the ignition is on

  13. 13. Check the ground connection for the ignition coil to ensure it is solid and free of corrosion

  14. 14. Inspect the Spark Plug

  15. 15. Remove the spark plug associated with ignition coil 'D' and inspect it for wear or damage. A fouled or damaged spark plug can cause issues with the ignition system

  16. 16. Replace the spark plug if necessary

  17. 17. Check for Engine Mechanical Issues

  18. 18. If the ignition coil and spark plug are functioning correctly, consider checking for other engine issues, such as a vacuum leak, low compression, or fuel delivery problems that could affect ignition performance

  19. 19. Clear the Codes and Test Drive

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

  21. 21. Take the vehicle for a test drive to see if the code returns

  22. 22. Consult a Professional

  23. 23. If the issue persists after following these steps, it may be necessary to consult a professional mechanic for further diagnosis. They may have specialized tools and knowledge to identify more complex issues. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the P231B code