• | 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. |
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 | P0099, P2199 |
Low Reference | -- | P0098, P0099 | P0098, P0099 | P0098, P0099 | P0099, P2199 |
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) |
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 5V 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 5V 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.
• | 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. |
The ECM detects that the difference in range between the IAT and the IAT sensor 2 is greater than 30°C (54°F) for greater than 4 seconds continuously or 50 seconds cumulative.
DTC P2199 is a Type B DTC.
DTC P2199 is a Type B DTC.
• | 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. |
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information.
⇒ | 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 K20 ECM. |
⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 ECM. |
⇒ | If greater than the specified range, test the signal circuit for an open/high resistance. |
⇒ | If greater than the specified range, test the signal circuit for an open/high resistance. |
Measure and record the resistance of the B75B MAF/IAT sensor and the IAT sensor 2 at various ambient temperatures, then compare those measurements to the Temperature Versus Resistance.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for ECM replacement, setup, and programming |