Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC P2199: Intake Air Temperature (IAT) Sensor 1-2 CorrelationDiagnostic Fault Information
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
|---|---|---|---|---|---|
IAT Sensor Signal | P0112, P0114 | P0113, P0114 | P0113, P0114 | P0113, P0114 | P0114, P2199 |
Low Reference | -- | P0113, P0114 | P0113, P0114 | P0113, P0114 | P0114, P2199 |
IAT Sensor 2 Signal | P0097, P0099 | P0098, P0099 | P0098, P0099 | P0098, P0099 | P0096, P0099, P2199 |
Low Reference | -- | P0098, P0099 | P0098, P0099 | P0098, P0099 | P0096, P0099, P2199 |
Typical Scan Tool Data
Circuit | Short to Ground | Open | Short to Voltage |
|---|---|---|---|
Operating Conditions: Engine Running Parameter Normal Range: Varies with ambient temperature | |||
IAT Sensor Signal | 143°C (289°F) | -40°C (-40°F) | -40°C (-40°F) |
Low Reference | -- | -40°C (-40°F) | -40°C (-40°F) |
Circuit | Short to Ground | Open | Short to Voltage |
|---|---|---|---|
Operating Conditions: Engine running Parameter Normal Range: Varies with ambient temperature | |||
IAT Sensor 2 Signal | 143°C (289°F) | -40°C (-40°F) | -40°C (-40°F) |
Low Reference | -- | -40°C (-40°F) | -40°C (-40°F) |
Circuit/System Description
The intake air temperature (IAT) sensor is integrated with the mass air flow (MAF) sensor. The IAT sensor is a variable resistor that measures the temperature of the air when it first enters the induction system. This sensor is also used to calculate ambient air temperature. The engine control module (ECM) supplies 5 volts to the IAT sensor signal circuit and a ground for the low reference circuit.
The intake air temperature (IAT) sensor 2 is integrated with the intake air pressure and temperature sensor. The IAT sensor 2 is a variable resistor that measures the temperature of the air after the turbocharger and the charge air cooler, and before it enters the engine intake manifold. The engine control module (ECM) supplies 5 volts to the IAT sensor 2 signal circuit and a ground for the low reference circuit.
The purpose of this diagnostic is to analyze the performance of the 2 sensors by comparing them to each other under various operating conditions to determine if they are within an acceptable temperature range of each other.
Conditions for Running the DTC
| • | The engine is running. |
| • | The MAF is between 9-50 g/s. |
| • | The vehicle speed is greater than 71 km/h (44 mph). |
| • | The boost pressure to barometric (BARO) pressure ratio is less than 1.4. |
| • | The above conditions must be met for greater than 20 seconds. |
| • | This DTC runs continuously within the enabling conditions. |
Conditions for Setting the DTC
The ECM detects that the difference in range between the IAT and the IAT sensor 2 either plus or minus is greater than 20°C (36°F) for greater than 4 seconds continuously or 50 seconds cumulative.
Action Taken When the DTC Sets
DTC P2199 is a Type B DTC.
Conditions for Clearing the MIL/DTC
DTC P2199 is a Type B DTC.
Diagnostic Aids
| • | When the engine is cold, at ignition ON, a properly functioning IAT sensor will gradually increase the scan tool IAT Sensor parameter. This is due to the heat that is generated by the MAF sensor heating elements. |
| • | Depending on the ambient temperature, an IAT sensor signal circuit that is shorted to the MAF sensor signal circuit can cause either a rapid fluctuation in the IAT Sensor parameter or cause it to become stuck at a given value. |
| • | An IAT low reference circuit that is open can cause the IAT Sensor parameter response to be sluggish. |
| • | An IAT sensor 2 signal circuit that is shorted to the intake air pressure signal circuit can cause the IAT Sensor 2 parameter response to be sluggish or become stuck at a given value. |
Reference Information
Schematic Reference
Connector End View Reference
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
- If the ignition has been OFF for 8 hours or greater, the IAT sensor, the IAT sensor 2 and the engine coolant temperature (ECT) sensor should be within 9°C (16°F) of each other. Ignition ON, observe the scan tool IAT Sensor, IAT Sensor 2 and the ECT Sensor parameters. Compare those sensor parameters to each other to determine if the condition is current.
- Engine running, observe the scan tool IAT Sensor 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.
- Engine running, observe the scan tool IAT Sensor 2 parameter. The reading should be between -39 to +130°C (-38 to +266°F) depending on the current ambient temperature and the vehicle operating conditions.
- 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
- Verify that the induction system components are properly positioned and connected.
- Ignition OFF, disconnect the harness connector at the MAF/IAT sensor.
- Ignition OFF for 90 seconds, test for less than 5 ohms between the MAF sensor ground circuit terminal B and ground.
- Test for less than 5 ohms between the IAT low reference circuit terminal D and ground.
- Disconnect the harness connector at the intake air pressure and temperature sensor.
- Test for less than 5 ohms between the low reference circuit terminal 1 or A and ground.
- Disconnect the ECM.
- Test for less than 5 ohms between the IAT sensor signal circuit terminal E and the ECM connector X2, terminal 50.
- Test for less than 5 ohms between the IAT sensor 2 signal circuit terminal 2 or B and the ECM connector X1, terminal 86.
- If the circuits test normal, test both the IAT sensor and the IAT sensor 2.
| ⇒ | If greater than the specified range, test the MAF sensor ground circuit for an open/high resistance. |
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
| ⇒ | If greater than the specified range, test the IAT sensor signal circuit for an open/high resistance. |
| ⇒ | If greater than the specified range, test the IAT sensor 2 signal circuit for an open/high resistance. |
Component Testing
Measure and record the resistance of the IAT sensor and the IAT sensor 2 at various ambient temperatures, then compare those measurements to the Temperature vs Resistance table. Refer to Temperature Versus Resistance.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for ECM replacement, setup, and programming |
