P0663: Intake Air Temperature Sensor 1 Circuit High

Definition

The OBD2 code P0663 indicates that the Intake Air Temperature Sensor 1 circuit is experiencing a high voltage condition, which may suggest a malfunction in the sensor or its wiring

Common causes

Faulty intake air temperature sensor
Open or shorted wiring in the sensor circuit
Poor electrical connections or corroded connectors
Faulty engine control module (ECM)
High resistance in the sensor circuit
Incorrect sensor installation or positioning

Common misdiagnoses

Faulty Intake Air Temperature Sensor
Wiring issues or short circuits in the sensor circuit
Engine Control Module (ECM) malfunction
Air intake duct leaks
Mass Air Flow (MAF) sensor issues
Throttle position sensor problems
Vacuum leaks
Coolant temperature sensor faults

Troubleshooting steps

1. Check for Additional Codes

Before proceeding, check for any other related trouble codes that may provide more context to the issue
2. Inspect the IAT Sensor
3. Locate the IAT sensor, which is usually found in the intake manifold or air intake duct
4. Check for physical damage, corrosion, or loose connections at the sensor
5. Check Wiring and Connectors
6. Inspect the wiring harness and connectors leading to the IAT sensor for any signs of wear, fraying, or damage
7. Ensure that the connectors are securely attached and free of corrosion
8. Test the IAT Sensor
9. Use a multimeter to measure the resistance of the IAT sensor. Compare the readings to the manufacturer's specifications. A faulty sensor may show resistance values outside the specified range
10. If possible, test the sensor's output voltage while the engine is running. The voltage should change with temperature; if it remains high or does not change, the sensor may be faulty
11. Check the Engine Control Module (ECM)
12. Inspect the ECM for any signs of damage or corrosion, especially at the connector pins
13. Ensure that the ECM is functioning properly and that there are no software issues
14. Inspect the Air Intake System
15. Check for any air leaks in the intake system that could affect sensor readings
16. Ensure that the air filter is clean and not obstructing airflow
17. Clear the Codes and Test Drive
18. After performing the checks and repairs, clear the trouble codes using an OBD-II scanner
19. Take the vehicle for a test drive to see if the code reappears
20. Consult Technical Service Bulletins (TSBs)
21. Check for any TSBs related to the P0663 code for your specific vehicle make and model, as there may be known issues or recalls
22. Seek Professional Help
23. If the issue persists after performing the above steps, it may be necessary to consult a professional mechanic for further diagnosis. By following these steps, you should be able to identify and resolve the issue related to the P0663 code

Definition

Common causes

Common misdiagnoses

Troubleshooting steps

1. Check for Additional Codes

2. Inspect the IAT Sensor

3. Locate the IAT sensor, which is usually found in the intake manifold or air intake duct

4. Check for physical damage, corrosion, or loose connections at the sensor

5. Check Wiring and Connectors

6. Inspect the wiring harness and connectors leading to the IAT sensor for any signs of wear, fraying, or damage

7. Ensure that the connectors are securely attached and free of corrosion

8. Test the IAT Sensor

9. Use a multimeter to measure the resistance of the IAT sensor. Compare the readings to the manufacturer's specifications. A faulty sensor may show resistance values outside the specified range

10. If possible, test the sensor's output voltage while the engine is running. The voltage should change with temperature; if it remains high or does not change, the sensor may be faulty

11. Check the Engine Control Module (ECM)

12. Inspect the ECM for any signs of damage or corrosion, especially at the connector pins

13. Ensure that the ECM is functioning properly and that there are no software issues

14. Inspect the Air Intake System

15. Check for any air leaks in the intake system that could affect sensor readings

16. Ensure that the air filter is clean and not obstructing airflow

17. Clear the Codes and Test Drive

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

19. Take the vehicle for a test drive to see if the code reappears

20. Consult Technical Service Bulletins (TSBs)

21. Check for any TSBs related to the P0663 code for your specific vehicle make and model, as there may be known issues or recalls

22. Seek Professional Help

23. If the issue persists after performing the above steps, it may be necessary to consult a professional mechanic for further diagnosis. By following these steps, you should be able to identify and resolve the issue related to the P0663 code