P0111
DTC P0111 INTAKE AIR TEMPERATURE SENSOR1 CIRCUIT RANGE/PERFORMANCEComponent Location:
GENERAL DESCRIPTION
The Intake Air Temperature Sensor (IATS) is installed on the Intake Manifold Assembly. The IATS uses a thermistor whose resistance changes with the temperature. The electrical resistance of the IATS decreases as the temperature increases, and increases as the temperature decreases. The 5 V power source in the ECM is supplied to the IATS via a resistor in the ECM. That is, the resistor in the ECM and the thermistor in the IATS are connected in series. When the resistance value of the thermistor in IATS changes according to the intake air temperature, the signal voltage also changes. Using this signal, the information of the intake air temperature, the ECM corrects basic fuel injection duration and ignition timing.
DTC DESCRIPTION
The purpose of this diagnosis is to detect a stuck air temperature signal. The diagnostic function checks whether after a variation of the calculated air temperature also a variation of the measured air temperature is detected.
ECM sets DTC P0111 when the variation of measured intake air temperature is smaller than threshold while variation of calculated intake air temperature by ECM is greater than threshold.
DTC Detecting Condition:
Specification:
Schematic Diagram:
Signal Waveform:
MONITOR DTC STATUS
1. Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode.
2. Press F4(DTAL) to select DTC information from the DTCs menu.
3. Confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions.
4. Read "DTC Status" parameter.
5. Is parameter displayed "History(Not Present) fault"?
NOTE:
- History (Not Present) fault: DTC occurred but has been cleared.
- Present fault: DTC is occurring at present time.
YES: Fault is intermittent caused by poor contact in the sensor's and/or ECM's connector or was repaired and ECM memory was not cleared. Thoroughly check connectors for loose or poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Go to next step as below
TERMINAL AND CONNECTOR INSPECTION
1. Ignition "OFF".
2. Disconnect IATS connector.
3. Many malfunctions in the electrical system are caused by poor harness(es) and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
4. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
5. Has a problem been found?
YES: Repair as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Go to "Component Inspection" procedure.
COMPONENT INSPECTION
1. Measure resistance between terminals 1 and 2 of the sensor connector(Component side).
Specification:
2. Is IAT sensor data within the specification?
YES: Check for poor connection between ECM and component: backed out terminal, improper mating, broken locks or poor terminal to wire connection. Repair as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Check IAT sensor for contamination, deterioration, or damage. Substitute with a known-good IAT sensor and check for proper operation. If the problem is corrected, replace IAT sensor and then go to "Verification of Vehicle Repair" procedure.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode.
2. Press F4DTAL) and confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions.
3. Read "DTC Status" parameter.
4. Is parameter displayed "History(Not Present) fault".?
YES: System performing to specification at this time. Clear the DTC.
NO: Go to the applicable troubleshooting procedure.