P0113

DTC P0113 Intake Air Temperature Sensor (IAT) Diagnostic Chart:

IAT & TFT:

CIRCUIT DESCRIPTION
The Intake Air Temperature (IAT) sensor is a thermistor. The Powertrain Control Module (PCM) applies 5 volts on CKT 472 to the sensor. When the intake air is cold, the sensor resistance is high and the PCM will measure a high signal voltage. If the air is warm, the sensor resistance is low causing the PCM to measure a low voltage.

DIAGNOSTIC TROUBLE CODE (DTC) PO113 WILL SET WHEN
^ Signal voltage indicates an intake air temperature greater than 140°C (284°F).
^ Vehicle speed is greater than 35 mph.
^ Both of the above requirements are met for at least 5 seconds.

ACTION TAKEN (PCM WILL DEFAULT TO)
With a current DTC P0113 set, the PCM will use a default value of 17°C (63°F) for intake air temperature. DTC P0113 does not illuminate the Malfunction Indicator Lamp (MIL).


DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. A Tech 1 scan tool may be used to diagnose this fault since the PCM transmits "actual" values when the fault is present. A grounded circuit will cause the scan tool to display a temperature of approximately 147°C (297°F).
2. If the scan tool displays -40° with the IAT sensor disconnected, the PCM and wiring are OK and the IAT sensor must be replaced.

DIAGNOSTIC AIDS
An intermittent may be caused by a poor connection, rubbed through wire insulation or a wire broken inside the insulation.

Check for:
^ Poor connection or damaged harness - Inspect PCM harness for short to ground in CKT 472, improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection, and damaged harness.

^ Intermittent test - Observe IAT in scan tool while moving related connectors and wiring harness with warm engine running. If the failure is induced, the IAT display will change to a 147°C (297°F) temperature reading. This may help isolate the location of the malfunction.