Circuit Description

The in-car air temperature sensor (located under left side of dash, near steering column) is a thermistor that controls signal voltage to Instrument Panel Integration Module (IPM). Sensor contains an electric fan which pulls air from passenger compartment to sensor. The IPM applies voltage on circuit No. 734 (Dark Green wire), between in-car air temperature sensor and IPM. See WIRING DIAGRAMS  .

When sensor is cold, resistance is high and IPM will sense a high voltage signal at IPM harness connector terminal B4 (Dark Green wire). When sensor warms up, resistance is reduced and signal voltage is pulled low through circuit No. 61 (Yellow wire), between IPC and sensor.

Signal voltage varies from 5 volts (open circuit) to zero volt (shorted circuit). DTC will set when ignition is on or when circuit is open or shorted.