Intake Air Temperature (IAT) Sensor
If an IAT sensor-related code is present, perform appropriate DTC test. See TESTS W/CODES article. An out-of-calibration sensor may not set a trouble code. Use following procedure to test calibration. Disconnect IAT sensor harness connector. Measure resistance between IAT sensor terminals. Sensor resistance should be as specified. See IAT SENSOR RESISTANCE VALUES table. Resistance should be high when air temperature is cold and drop as air temperature warms. With vehicle sitting overnight, IAT sensor and coolant sensor should have close to the same resistance reading.
IAT SENSOR RESISTANCE VALUES
| Temperature °F (°C) | Ohms |
|---|---|
| 212 (100) | 177 |
| 158 (70) | 467 |
| 104 (40) | 1459 |
| 68 (20) | 3520 |
| 32 (0) | 9420 |
| 5 (-15) | 21,450 |
| -40 (-40) | 100,700 |
NOTE:
Ensure oil is okay before performing engine oil level sensor/switch diagnosis.