Diagnostic Instructions

DTC Descriptors

DTC P0097: Intake Air Temperature (IAT) Sensor 2 Circuit Low Voltage

DTC P0098: Intake Air Temperature (IAT) Sensor 2 Circuit High Voltage

Diagnostic Fault Information

Circuit	Short to Ground	Open	High Resistance	Short to Voltage	Signal Performance
IAT Sensor 2 Signal	P0097	P0098	P0116	P0098*	P0098, P0116
IAT Sensor 2 Low Reference	--	P0098	P0116	P0098*	--
*Internal ECM or sensor damage may occur if the circuit is shorted to B+.

Typical Scan Tool Data

IAT Sensor 2

Circuit	Short to Ground	Open	Short to Voltage
Operating Conditions: Ignition ON or Engine Running Parameter Normal Range: -39 to +120°C (-38 to +248°F)
IAT Sensor 2 Signal	139°C (282°F)	-40°C (-40°F)	-40°C (-40°F)
IAT Sensor 2 Low Reference	--	-40°C (-40°F)	-40°C (-40°F)

Circuit/System Description

The intake air temperature (IAT) sensor 2 is a variable resistor that measures the temperature of the air in the engine intake manifold. The engine control module (ECM) supplies 5 volts to the IAT sensor 2 signal circuit, and a ground for the IAT sensor 2 low reference circuit. The ECM continuously monitors the IAT sensor 2 signal voltage for an excessively high or low voltage, or a voltage signal that is not in correlation with the engine coolant temperature (ECT) sensor.

Conditions for Running the DTC

Conditions for Setting the DTC

P0097

The IAT sensor 2 is greater than 148°C (298°F) for greater than 1 second. This is equal to or less than 0.10 volt on the IAT sensor 2 signal circuit as measured by the ECM.

P0098

The IAT sensor 2 is less than -39°C (-38°F) for greater than 1 second. This is equal to or greater than 4.8 volts on the IAT sensor 2 signal circuit as measured by the ECM.

Action Taken When the DTC Sets

Conditions for Clearing the DTC

DTCs P0097 and P0098 are Type B DTCs.

Diagnostic Aids

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, observe the scan tool IAT Sensor 2 parameter. The reading should be between -39 to 120°C (-38 to +248°F) depending on the current ambient temperature and the vehicle operating conditions.
2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the IAT sensor 2.
2. Ignition OFF, for 90 seconds, test for less than 5 ohms between the low reference circuit terminal B and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

3. Ignition ON, verify the scan tool IAT Sensor 2 parameter is less than -39°C (-38°F).

⇒	If greater than the specified range, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the ECM.

4. Install a 3A fused jumper wire between the signal circuit terminal A and the low reference circuit terminal B. Verify the scan tool IAT Sensor 2 parameter is greater than 130°C (266°F).

⇒	If less than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.

5. If all circuits test normal, test or replace the IAT sensor 2.

Component Testing

Static Test

1. Ignition OFF, disconnect the harness connector at the IAT sensor 2.
2. Measure the resistance between the signal terminal A and the low reference circuit terminal B.
3. Compare the value to the Temperature Vs Resistance table. Verify the resistance is within 9 percent of the specification. Refer to Temperature Versus Resistance.

⇒	If not within the specified range, replace the IAT sensor 2.

Dynamic Test

Important: A thermometer can be used to test the sensor off the vehicle in heated water.

1. Test the IAT sensor 2 by varying the sensor temperature while monitoring the sensor resistance.
2. Compare the readings with the Temperature Vs Resistance table and verify that the resistance is within 9 percent of the specification.

⇒	If not within the specified range, replace the IAT sensor 2.

Repair Instructions

Repair Verification

1. Install any components or connectors that have been removed or replaced during diagnosis.
2. Perform any adjustment, programming, or setup procedures that are required when a component or module is removed or replaced.
3. Clear the DTCs.
4. Turn OFF the ignition for 90 seconds.
5. Duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.
6. Engine running, observe the scan tool Soot Mass parameter.

⇒	If the Soot Mass value is less than 30 grams, perform the. Diesel Particulate Filter (DPF) Regeneration Enable.

⇒	If the Soot Mass value is greater than 30 grams, perform the. Diesel Particulate Filter (DPF) Service Regeneration.