WOMS
P code powertrain Medium severity

P1475 Fan Relay (Low) Circuit Malfunction

The OBD2 code P1475 indicates a malfunction in the low circuit of the fan relay, which may affect the operation of the engine cooling fan

Definition

The OBD2 code P1475 indicates a malfunction in the low circuit of the fan relay, which may affect the operation of the engine cooling fan

Common causes

  • Faulty fan relay
  • Damaged wiring or connectors
  • Short circuit in the fan circuit
  • Open circuit in the fan circuit
  • Faulty engine control module (ECM)
  • Blown fuse
  • Poor ground connection

Common misdiagnoses

  • Faulty fan motor
  • Bad temperature sensor
  • Wiring issues or shorts
  • Faulty engine control module (ECM)
  • Incorrect coolant levels
  • Thermostat malfunction
  • Air conditioning system issues
  • Relay problems unrelated to the fan circuit

Troubleshooting steps

  1. 1. Check the Code and Freeze Frame Data

    Use an OBD-II scanner to confirm the P1475 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. Inspect the Wiring and Connectors

    Visually inspect the wiring and connectors related to the fan relay and cooling fan. Look for signs of damage, corrosion, or loose connections

  4. 4. Pay special attention to the ground connections, as poor grounding can lead to low voltage issues

  5. 5. Test the Fan Relay

    Locate the fan relay and test it using a multimeter. Check for continuity and ensure that it operates correctly when energized

  6. 6. If the relay is faulty, replace it with a new one

  7. 7. Check the Cooling Fan

    Test the cooling fan directly by applying power to it to see if it operates. If it does not run, the fan may be faulty and needs replacement

  8. 8. If the fan operates, check the fan motor for any signs of wear or damage

  9. 9. Measure Voltage at the Relay

    With the ignition on, measure the voltage at the relay terminals. You should see battery voltage at the input terminal

  10. 10. If the voltage is low or absent, trace the wiring back to the power source and check for any breaks or shorts

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

    If all other components check out, the issue may lie with the ECM. Ensure that the ECM is functioning properly and that it is sending the correct signals to the fan relay

  12. 12. Check for any software updates or recalls related to the ECM

  13. 13. Check for Short Circuits

    Inspect the circuit for any short circuits that could be causing a low voltage condition. Use a multimeter to check for continuity between the relay circuit and ground

  14. 14. Clear the Code and Test Drive

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

  15. 15. Consult a Professional

    If the issue persists after following these steps, it may be best to consult a professional mechanic or technician who has experience with your specific vehicle make and model. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the P1475 code