Intake Air Temperature Sensor Operation

Fig. 16 Intake Air Temperature Sensor And MAP Sensor:

PURPOSE
The intake air temperature sensor measures the temperature of the air as it enters the engine. The sensor supplies one of the inputs the PCM uses to determine injector pulse-width.

CIRCUIT OPERATION
The intake air temperature sensor provides an input to the Powertrain Control Module (PCM) on circuit K21. Circuit K21 connects to cavity 6 of the PCM, and cavity 1 of the sensor connector.

From circuit K21, the intake air temperature sensor draws voltage from the PCM. The sensor is a variable resistor. As intake air temperature changes, the resistance in the sensor changes, causing a change in current draw.

The PCM provides a ground for the intake air temperature sensor signal (circuit K21) through circuit K4. Circuit K4 connects to cavity 51 of the PCM connector, and splices to the sensor connector.