| • | 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 2 Signal  | P0097  | P0096  | P0098  | P0098  | P0096  | 
Low Reference  | --  | P0096  | P0098  | --  | P0096  | 
Circuit  | Short to Ground  | High Resistance  | Open  | Short to Voltage  | 
|---|---|---|---|---|
IAT Sensor Signal  | P0112  | P0113  | P0113  | P0113  | 
Low Reference  | --  | P0113  | P0113  | P0113  | 
Circuit  | Short to Ground  | Open  | Short to Voltage  | 
|---|---|---|---|
Operating Conditions: Key ON, engine OFF Parameter Normal Range: Varies between -39 to +120°C (-38 to +248°F)  | |||
IAT Sensor 2 Signal  | 150°C (300°F)  | -40°C (-40°F)  | -40°C (-40°F)  | 
Low Reference  | --  | -40°C (-40°F)  | -40°C (-40°F)  | 
Circuit  | Short to Ground  | Open or High Resistance  | Short to Voltage  | 
|---|---|---|---|
Parameter Normal Range: Varies between -39 to +120°C (-38 to +248°F)  | |||
IAT Sensor 1 Signal  | 140°C (284°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 2 is a variable resistor. The IAT sensor 2 measures the temperature of the air at 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. 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 sensor 2 signal circuit. With lower sensor resistance, the ECM detects a lower voltage on the IAT sensor 2 signal circuit. The ECM monitors the IAT sensor 2 and the IAT sensor signal voltages for a voltage that is not within a calibrated range of each other.
| • | DTCs P0097, P0098, P0112, P0113, P0116, P0117, P0118, P0128, P0500, P0502, P0603 are not set. | 
| • | DTC P0116 has run and passed. | 
| • | The engine has been OFF for more than 8 hours. | 
| • | The IAT sensor is more than 10°C (50°F). | 
| • | DTC P0096 runs once per key cycle within the enabling conditions. | 
| • | DTC P0116 must run and pass. | 
| • | At start-up, after an 8 hour engine soak time, the IAT sensor 2 temperature is more than 20°C (36°F) higher or lower than the IAT sensor. | 
DTC P0096 is a Type B DTC.
DTC P0096 is a Type B DTC.
| • | An IAT sensor that is skewed lower at various ambient temperatures, due to more resistance than is normal, can widen the spread between the 2 sensors and cause this DTC to set. Measure and record the resistance of the IAT sensor and IAT sensor 2 at various ambient temperatures, and then compare those measurements to the Temperature vs. Resistance Table. Refer to Temperature Versus Resistance . | 
| • | Inspect both IAT sensors terminals, for corrosion or a poor connection. | 
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Important: Perform this verification procedure only if the ignition has been OFF for eight hours or more.
| ⇒ | 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, repair the open/high resistance in the circuit. | 
| ⇒ | If greater than the specified range, repair the open/high resistance in the circuit. | 
| ⇒ | If the difference is more than 9 percent, replace the IAT sensor 2. | 
| ⇒ | If the difference is more than 9 percent, replace the MAF/IAT sensor. | 
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for ECM replacement, setup, and programming |