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P code powertrain Medium severity

P008C Fuel Cooler Pump Control Circuit Open

The OBD2 code P008C indicates that there is an open circuit in the fuel cooler pump control circuit, meaning the engine control module (ECM) is not receiving the expected signal or voltage from the fuel cooler pump...

Definition

The OBD2 code P008C indicates that there is an open circuit in the fuel cooler pump control circuit, meaning the engine control module (ECM) is not receiving the expected signal or voltage from the fuel cooler pump circuit, which can affect fuel temperature regulation

Common causes

  • Faulty fuel cooler pump
  • Open or damaged wiring
  • Poor electrical connections
  • Failed fuel cooler pump relay
  • Blown fuse
  • Faulty engine control module (ECM)

Common misdiagnoses

  • Fuel pump failure
  • Fuel pressure regulator issues
  • Fuel injector problems
  • Wiring or connector issues
  • Engine control module (ECM) faults
  • Fuel filter blockage
  • Fuel line leaks
  • Other fuel system component failures

Troubleshooting steps

  1. 1. Check the Code and Freeze Frame Data

    Use an OBD-II scanner to confirm the P008C code and check for any additional codes that may provide more context

  2. 2. Review freeze frame data to understand the conditions under which the code was set

  3. 3. Visual Inspection

    Inspect the wiring and connectors related to the fuel cooler pump. Look for signs of damage, corrosion, or loose connections

  4. 4. Check the fuel cooler pump itself for any physical damage

  5. 5. Test the Fuel Cooler Pump

    If accessible, test the fuel cooler pump directly by applying power to it to see if it operates. If it does not work, the pump may need to be replaced

  6. 6. Measure the resistance of the pump to ensure it is within the manufacturer's specifications

  7. 7. Check the Control Circuit

    Use a multimeter to check for continuity in the wiring between the engine control module (ECM) and the fuel cooler pump

  8. 8. Inspect for any breaks, shorts, or opens in the wiring harness

  9. 9. Inspect the ECM

    Check the ECM for any signs of damage or corrosion, especially at the connectors

  10. 10. If possible, test the output signal from the ECM to the fuel cooler pump to ensure it is sending the correct signal

  11. 11. Check for Ground Issues

    Ensure that the fuel cooler pump has a good ground connection. A poor ground can cause the circuit to appear open

  12. 12. Test the ground wire for continuity and resistance

  13. 13. Look for Related Issues

    Check for any other related codes that may indicate a broader issue with the fuel system or electrical system

  14. 14. Inspect the fuel system for any other potential problems, such as fuel leaks or blockages

  15. 15. Clear the Code and Test Drive

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

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

  17. 17. Consult Technical Service Bulletins (TSBs)

    Check for any TSBs related to the P008C code for your specific vehicle make and model, as there may be known issues or recalls

  18. 18. Seek Professional Help

    If the issue persists after following these steps, it may be necessary to consult a professional mechanic or technician who has experience with your vehicle's specific systems. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the P008C code