P0113

Diagnostic Chart:

Schematic:

The Intake Air Temperature (IAT) sensor is a thermistor that varies resistance according to changes in air induction temperature. The PCM supplies a five volt reference through a pull-up resistor to the sensor, which is connected to ground. When the sensor is cold it has high resistance (high signal voltage at PCM). As the sensor temperature increases, its resistance decreases (lower signal voltage at PCM). The PCM uses the signal voltage to determine air induction temperature. DTC P0113 sets when the IAT sensor signal voltage at the PCM is above the calibrated voltage value (below the calibrated temperature value).

DTC PARAMETERS
DTC P0113 will set if IAT sensor temperature is less than -39°C (-38°F) when.
^ Condition exists for longer than 3 seconds
^ Engine run time is greater than 5 minutes and 20 seconds
^ ECT is greater than -40°C (-40°F)
^ Vehicle speed is less than 24 km/h (15 mph)
^ No ECT or vehicle speed DTCs has been set

DTC P0113 diagnostic runs continuously once the above conditions have been met.

P0113 is a (type B) DTC

DIAGNOSTIC AIDS
To locate an intermittent problem, use Scan tool to monitor IAT temperature with ignition On, engine Off. Wiggling wires while watching for a change in IAT temperature may locate the area where an open or short to voltage in the wiring could lie.

Refer to ECT General Description for a Temperature vs. Resistance chart.

NOTE: A short to B+ on signal circuit 472 Will damage and melt the IAT sensor.