P0113

Diagnostic Chart:

Wiring Chart:

CIRCUIT DESCRIPTION

The Intake Air Temperature (IAT) sensor is a thermister that controls signal voltage to the PCM. When the air is cold, the sensor resistance is high, therefore the PCM will see a high signal voltage. As air warms, the sensor resistance becomes less and the voltage drops.

CONDITIONS FOR SETTING THE DTC

^ The engine has been operating for 8 minutes.

^ The IAT is less than or equal to -40°C (-40°F).

^ The conditions were met for 2 seconds.

ACTION TAKEN WHEN THE DTC SETS

^ The PCM illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive drive trip the diagnostic runs and fails.

^ The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the Failure Records store this information. If the diagnostic reports a failure on the second consecutive drive trip, the Freeze Frame records the operating conditions at the time of failure and updates the Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC

^ The PCM will turn the MIL off after three consecutive trips without a fault condition.

^ A History DTC will clear after forty consecutive warm-up cycles during which the diagnostic does not fail (the coolant temperature has risen 5°C (40°F) from start up coolant temperature and engine coolant temperature exceeds 71°C (160°F) during that same ignition cycle).

^ Use of a Scan Tool will clear the DTC codes.

DIAGNOSTIC AIDS

The scan tool displays intake air temperature in degrees centigrade. Refer to Symptoms. Testing and Inspection

A skewed sensor could result in poor driveability complaints. Refer to Specifications / Electrical / Temperature vs Resistance.

TEST DESCRIPTION

Number(s) below refer to the step number(s) on the Diagnostic Table.

2. This step determines if P0113 is a hard failure or an intermittent condition.

3. This step will determine if there is a wiring problem or a malfunctioning PCM.

9. This step determines if there is a short to voltage on the signal circuit. A short to voltage increases current flow through the sensor which 'overwhelms' the sensor. This doesn't allow the sensor to pull-down the circuit to the correct voltage and thus display the correct temperature.

10. After repairing the short to voltage, check the sensor for proper operation.