WOMS
P code powertrain Medium severity

P240E Evaporative Emission System Leak Detection Pump Control Circuit Low

The OBD2 code P240E indicates a problem with the evaporative emission system's leak detection pump control circuit, specifically that the circuit is reading a low voltage or signal, which may suggest a malfunction in...

Definition

The OBD2 code P240E indicates a problem with the evaporative emission system's leak detection pump control circuit, specifically that the circuit is reading a low voltage or signal, which may suggest a malfunction in the pump or its wiring

Common causes

  • Faulty leak detection pump
  • Damaged or corroded wiring
  • Poor electrical connections
  • Failed relay
  • Blown fuse
  • Vacuum leaks in the evaporative system
  • Faulty engine control module (ECM)

Common misdiagnoses

  • Faulty Evaporative Emission System Leak Detection Pump
  • Damaged or corroded wiring/connectors in the control circuit
  • Faulty Engine Control Module (ECM)
  • Vacuum leaks in the evaporative system
  • Malfunctioning fuel cap or seal
  • Issues with the charcoal canister
  • Faulty pressure sensor in the evaporative system
  • Incorrectly installed or damaged hoses in the evaporative system

Troubleshooting steps

  1. 1. Visual Inspection

    Wiring and Connectors: Check the wiring and connectors related to the leak detection pump for any signs of damage, corrosion, or loose connections

  2. 2. Pump Condition

    Inspect the leak detection pump itself for any physical damage or signs of wear

  3. 3. Check for Additional Codes

    Use an OBD-II scanner to check for any other related trouble codes that may provide more context or indicate additional issues

  4. 4. Test the Leak Detection Pump

    Functionality: If possible, test the leak detection pump to ensure it operates correctly. You may need to apply power directly to the pump to see if it activates

  5. 5. Resistance Check

    Measure the resistance of the pump using a multimeter. Compare the reading to the manufacturer's specifications

  6. 6. Inspect the Evaporative Emission System

    Hoses and Connections: Check all hoses and connections in the evaporative emission system for cracks, leaks, or disconnections

  7. 7. Charcoal Canister

    Inspect the charcoal canister for damage or blockages

  8. 8. Check the Control Circuit

    Voltage and Ground: Use a multimeter to check for proper voltage and ground at the leak detection pump connector. Ensure that the control circuit is receiving the correct signals from the Engine Control Module (ECM)

  9. 9. Continuity Test

    Perform a continuity test on the wiring between the ECM and the leak detection pump to ensure there are no breaks in the circuit

  10. 10. Inspect the Engine Control Module (ECM)

    If all other components check out, there may be an issue with the ECM itself. Check for any software updates or known issues with the ECM related to the evaporative emission system

  11. 11. Clear Codes and Test Drive

    After performing repairs or replacements, clear the trouble codes using the OBD-II scanner and take the vehicle for a test drive to see if the code returns

  12. 12. Professional Diagnosis

    If the issue persists after performing the above steps, consider seeking help from a professional mechanic or technician who has experience with the specific vehicle make and model.Additional Tips: - Always refer to the vehicle's service manual for specific diagnostic procedures and specifications. - Ensure that you are working in a safe environment and taking necessary precautions when handling electrical components and systems. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the P240E code