DTC Advanced Diagnostics: P0111
DTC P0111:Intake Air Temperature (IAT) Sensor 1 Circuit Range/Performance Problem

General Description


Intake air temperature (IAT) sensor 1 is a thermistor that detects intake air temperature, and it is used for air/fuel ratio feedback control to compensate for the atmospheric density fluctuations that accompany changes in intake air temperature. IAT sensor 1 resistance varies depending on temperature. The output voltage and the sensor resistance increase as the intake air temperature decreases. Conversely, the output voltage and the sensor resistance decrease as the intake air temperature increases. If the intake air temperature is a specified value for a specified time, the powertrain control module (PCM) detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type
Execution
Continuous
Sequence
None
Duration
3.0 seconds or more
DTC Type
Two drive cycles, MIL on

Enable Conditions
Condition
 
Vehicle
ON mode

Malfunction Threshold
The intake air temperature [IAT Sensor (1)] is 285 °F (141 °C) or more for at least 3.0 seconds.

[ ]: HDS Parameter

Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
IAT sensor 1 failure (range/performance problem)
PCM internal circuit failure

Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.