P0098

DTC P0097 or P0098

Diagnostic Instructions

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

* The ignition is ON or the engine is running.
* The DTCs run continuously when the enabling conditions are met.

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

DTCs P0097 and P0098 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0097 and P0098 are Type B DTCs.

Diagnostic Aids

* If the engine has sat overnight, the IAT sensor 2 and the ECT sensor values should display within 15°C (27°F).
* High resistance on either the IAT sensor 2 signal circuit or the IAT sensor 2 low reference circuit could set this DTC.

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 (EGR Temperature Sensors) Temperature Versus Resistance (Fuel Temperature Sensor) Temperature Versus Resistance (IAT Sensor 1) Temperature Versus Resistance (ECT Sensors) Temperature Versus Resistance (IAT Sensor 2) Temperature Versus Resistance (EGT Sensors).

^ 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

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

* Intake Air Temperature (IAT) Sensor 2 Replacement