WOMS
P code powertrain High severity

P0727 Engine Speed Input Circuit No Signal

The OBD2 code P0727 indicates that the engine control module (ECM) is not receiving a signal from the engine speed input circuit, which typically relates to the vehicle's crankshaft or camshaft position sensor

Definition

The OBD2 code P0727 indicates that the engine control module (ECM) is not receiving a signal from the engine speed input circuit, which typically relates to the vehicle's crankshaft or camshaft position sensor

Common causes

  • Faulty engine speed sensor
  • Damaged wiring or connectors in the engine speed input circuit
  • Failed powertrain control module (PCM)
  • Poor electrical connections
  • Faulty transmission speed sensor
  • Malfunctioning transmission control module (TCM)
  • Issues with the vehicle's computer system or software
  • Mechanical issues in the transmission affecting sensor operation

Common misdiagnoses

  • Faulty Engine Control Module (ECM)
  • Faulty Transmission Control Module (TCM)
  • Bad crankshaft position sensor
  • Bad camshaft position sensor
  • Wiring issues or shorts in the harness
  • Faulty speed sensor
  • Transmission issues (e.g., internal failure)
  • Incorrectly installed or damaged connectors
  • Faulty ignition system components
  • Battery or charging system problems

Troubleshooting steps

  1. 1. Check for Additional Codes

    Before proceeding, check for any other related trouble codes that may provide more context or indicate other issues

  2. 2. Inspect Wiring and Connectors

  3. 3. Visually inspect the wiring and connectors associated with the engine speed sensor. Look for signs of damage, corrosion, or loose connections

  4. 4. Ensure that the connectors are securely attached and that there are no broken wires

  5. 5. Test the Engine Speed Sensor

  6. 6. Use a multimeter to test the resistance of the engine speed sensor. Compare the readings to the specifications provided in the vehicle’s service manual

  7. 7. If the sensor is a Hall effect or magnetic type, check for proper voltage and signal output while the engine is running

  8. 8. Check the Power and Ground

  9. 9. Verify that the engine speed sensor is receiving the correct voltage from the ECM. Check the power supply and ground connections to the sensor

  10. 10. If there is no power or ground, trace the wiring back to the ECM to identify any breaks or shorts

  11. 11. Inspect the ECM

  12. 12. If the sensor and wiring are functioning correctly, the issue may lie with the ECM itself. Check for any signs of damage or corrosion on the ECM connectors

  13. 13. If possible, test the ECM with a scan tool to see if it is receiving signals from the engine speed sensor

  14. 14. Check for Mechanical Issues

  15. 15. Ensure that there are no mechanical issues affecting the engine speed sensor, such as a damaged reluctor ring or issues with the crankshaft or camshaft

  16. 16. Clear Codes and Test Drive

  17. 17. After performing the necessary repairs, clear the trouble codes using a scan tool and take the vehicle for a test drive to see if the code returns

  18. 18. Consult a Professional

  19. 19. If the issue persists after following 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 P0727 code