WOMS
P code powertrain Medium severity

P0577 Cruise Control Input Circuit Low Input

The OBD2 code P0577 indicates that there is a low voltage signal detected in the cruise control input circuit, which may suggest a malfunction in the cruise control system or its components

Definition

The OBD2 code P0577 indicates that there is a low voltage signal detected in the cruise control input circuit, which may suggest a malfunction in the cruise control system or its components

Common causes

  • Faulty cruise control switch
  • Damaged wiring or connectors in the cruise control circuit
  • Faulty brake pedal position switch
  • Malfunctioning throttle position sensor
  • Failed engine control module (ECM)
  • Poor ground connection in the cruise control system

Common misdiagnoses

  • Faulty cruise control switch
  • Malfunctioning brake light switch
  • Wiring issues or shorts in the circuit
  • Faulty throttle position sensor
  • Defective engine control module (ECM)
  • Issues with the accelerator pedal position sensor
  • Problems with the cruise control module

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 for the issue

  2. 2. Inspect Wiring and Connectors

  3. 3. Visually inspect the wiring and connectors related to the cruise control system. Look for frayed wires, corrosion, or loose connections

  4. 4. Pay special attention to the wiring harness that connects to the cruise control switch and the brake pedal switch

  5. 5. Test the Cruise Control Switch

  6. 6. Check the cruise control switch for proper operation. Use a multimeter to test for continuity and ensure that the switch is functioning correctly

  7. 7. If the switch is faulty, it may need to be replaced

  8. 8. Check the Brake Pedal Switch

  9. 9. The brake pedal switch is often involved in the cruise control system. Ensure that it is functioning properly and that it is not stuck in the "off" position

  10. 10. Test the switch for continuity and proper operation

  11. 11. Inspect the Cruise Control Module

  12. 12. If the wiring and switches are in good condition, the issue may lie within the cruise control module itself. Check for any signs of damage or malfunction

  13. 13. If possible, test the module with a scan tool to see if it is receiving and sending the correct signals

  14. 14. Check for Ground Issues

  15. 15. Ensure that all ground connections related to the cruise control system are secure and free of corrosion. Poor grounding can lead to low input signals

  16. 16. Test the Vehicle Speed Sensor (VSS)

  17. 17. The cruise control system relies on the vehicle speed sensor to function correctly. Test the VSS to ensure it is providing accurate readings

  18. 18. If the VSS is faulty, it may need to be replaced

  19. 19. Clear Codes and Test Drive

  20. 20. After performing the above checks and repairs, clear the trouble codes using the OBD-II scanner

  21. 21. Take the vehicle for a test drive to see if the code reappears. Monitor the cruise control system to ensure it is functioning properly

  22. 22. Consult a Professional

  23. 23. If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician who has experience with cruise control systems and OBD-II diagnostics. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the P0577 code