WOMS
P code powertrain High severity

P068D ECM/PCM Power Relay Sense Circuit Range/Performance Problem

The OBD2 code P068D indicates a problem with the power relay sense circuit for the Engine Control Module (ECM) or Powertrain Control Module (PCM), suggesting that the voltage levels are outside the expected range or not...

Definition

The OBD2 code P068D indicates a problem with the power relay sense circuit for the Engine Control Module (ECM) or Powertrain Control Module (PCM), suggesting that the voltage levels are outside the expected range or not performing as intended

Common causes

  • Faulty ECM/PCM power relay
  • Poor electrical connections or wiring issues
  • Faulty ECM/PCM
  • Low battery voltage
  • Corroded or damaged connectors
  • Short circuits in the power relay sense circuit
  • Open circuits in the power relay sense circuit
  • Faulty fuses related to the power relay circuit

Common misdiagnoses

  • Faulty ECM/PCM
  • Bad power relay
  • Wiring issues or shorts
  • Battery problems
  • Grounding issues
  • Faulty sensors
  • Corroded connectors
  • Software issues or updates needed

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 Battery and Charging System

    Ensure the battery is fully charged and in good condition

  3. 3. Check the alternator output to ensure it is providing adequate voltage

  4. 4. Inspect battery terminals and cables for corrosion or loose connections

  5. 5. Examine the Power Relay

    Locate the ECM/PCM power relay in the fuse box or relay panel

  6. 6. Inspect the relay for any signs of damage or corrosion

  7. 7. Swap the relay with a similar one (if available) to see if the problem persists

  8. 8. Check Wiring and Connectors

    Inspect the wiring and connectors associated with the ECM/PCM power relay sense circuit for damage, fraying, or corrosion

  9. 9. Ensure all connections are secure and free of dirt or moisture

  10. 10. Test the Relay Operation

    Use a multimeter to test the relay for proper operation. Check for continuity and ensure it activates when power is applied

  11. 11. If the relay is not functioning correctly, replace it

  12. 12. Check the ECM/PCM

    Inspect the ECM/PCM for any signs of damage or water intrusion

  13. 13. Ensure that the ECM/PCM is properly grounded and that all connections are secure

  14. 14. Test the Power Supply

    Use a multimeter to check for proper voltage at the power relay and the ECM/PCM

  15. 15. Ensure that the relay is receiving the correct voltage when the ignition is turned on

  16. 16. Inspect Fuses

    Check the fuses related to the ECM/PCM and the power relay. Replace any blown fuses

  17. 17. Perform a Visual Inspection

    Look for any signs of physical damage to the wiring harness, connectors, or components in the engine bay

  18. 18. Clear Codes and Test Drive

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

  19. 19. Take the vehicle for a test drive to see if the code returns.1

  20. 20. Consult a Professional

    If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician for further diagnosis. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the P068D code. Always refer to the vehicle's service manual for specific procedures and specifications related to your make and model