Examination
1. The air temperature sensor is a thermistor that changes its resistance depending on the temperature. When the resistance of the thermistor changes, the value of the voltage removed from it also changes. As the temperature decreases, the resistance of the sensor increases, and as the temperature increases, it decreases. A malfunction of the air temperature sensor is detected by the diagnostic system and an appropriate code is generated in its memory.
4-cylinder engines and V-o motors from 1998 onwards
2. The sensor is screwed into the air cleaner (see fig. 1.1, a). Measure the resistance of the sensor. To do this, disconnect its electrical connector.
3. Measure the resistance at the sensor contacts. It should be in the range of 35.5-39.2 kΩ at room temperature (20°C). Start the engine or remove the sensor and heat it up with a hair dryer. The resistance of the sensor should decrease to the level of 7-8 kOhm at a temperature of 60°C. If the check gives different results, replace the sensor. If the engine was running with the connector disconnected, be sure to clear the fault code that occurred in this case.
V-engines produced from 1993 to 1997
4. Disconnect the air flow sensor electrical connector. Connect an ohmmeter to the IAT and GND pins (see fig. 5.3b). Resistance should be within 2-3 kΩ at room temperature (20°C). Start the engine or remove the sensor and heat it up with a hair dryer. The resistance of the sensor should decrease to the level of 400-700 ohms at a temperature of 60°C. If the check gives different results, replace the sensor. If the engine was running with the connector disconnected, be sure to clear the fault code that occurred in this case.
Replacement
5. Disconnect the negative cable from the battery.
Caution: If your vehicle's audio system is equipped with an anti-theft protection, make sure you know the unlock code before disconnecting the battery.
4-cylinder engines and V-engines production started from 1998
6. Disconnect the electrical connector from the sensor.
7. Remove the sensor from the air cleaner.
8. Installation of the sensor is carried out in the reverse order.
V-engines produced from 1993 to 1997
9. The air temperature sensor is part of the air flow sensor and is replaced as a single assembly.