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P0097



DTC P0097 or P0098

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.



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






Typical Scan Tool Data






Circuit/System Description

The intake air temperature (IAT) sensor 2 is a variable resistor. The IAT sensor 2 has a signal circuit and a low reference circuit. The IAT sensor measures the temperature of the air at the engines intake manifold. The engine control module (ECM) supplies 5 volts to the IAT 2 signal circuit, and a ground for the IAT 2 low reference circuit. When the IAT sensor 2 is cold, the sensor resistance is high. When the intake manifold air temperature increases, the sensor resistance decreases. With high sensor resistance, the ECM detects a high voltage on the IAT 2 signal circuit. With lower sensor resistance, the ECM detects a lower voltage on the IAT 2 signal circuit. The ECM continuously monitors the IAT signal voltage for an excessively high or low voltage, or a voltage signal that is not in correlation with the mass air flow (MAF)/IAT sensor.


Conditions for Running

* The engine run has been in operation for greater than 10 seconds.
* The engine coolant temperature (ECT) is less than 150°C (302°F).
* The vehicle speed is greater than 1 km/h (1 mph).
* The MAF is less than 512 g/s.
* DTC P0097 and P0098 run continuously within the enabling conditions



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 0.24 volt on the IAT sensor 2 signal circuit as measured by the ECM for P0097.

P0098

The IAT sensor 2 is less than -39°C (-38°F) for greater than 1 second. This is equal to or greater than 4.86 volts on the IAT signal circuit as measured by the ECM for P0098.


Action Taken When the DTC Sets

DTCs P0097 and P0098 are Type B DTCs.


Conditions for Clearing the MIL/DTC

DTCs P0097 and P0098 are Type B DTCs.


Reference Information
Schematic Reference

Engine Controls Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

DTC Type Definitions

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information


Circuit/System Verification

Important: Perform this verification procedure only if the ignition has been OFF for 8 hours or more.



1. Ignition ON, observe the scan tool IAT Sensor, IAT Sensor 2, and ECT Sensor parameters. The readings should be within 15°C (27°F) of each other, and also the ambient temperature.
2. Engine running, observe the DTC information with a scan tool. DTCs P0097 or P0098 should not set.
3. Operate the vehicle within the Conditions for Running the DTC. 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 for a short to ground. If the circuit tests normal, replace the ECM.

4. Install a 3A fused jumper wire between the signal circuit and the low reference circuit. 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 terminal A 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 IAT sensor 2.



Component Testing

Compare the IAT sensor 2 resistance to the values listed in the Temperature vs. Resistance table. Refer to Temperature Versus Resistance (Temperature Versus Resistance) .


Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Intake Air Temperature (IAT) Sensor 2 Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for ECM replacement, setup, and programming