P0111
DTC P0111 INTAKE AIR TEMPERATURE SENSOR 1 CIRCUIT RANGE/PERFORMANCEComponent Location:
COMPONENT LOCATION
GENERAL DESCRIPTION
The Intake Air Temperature (IAT) sensor measures the temperature of engine intake air. The Intake Air Temperature (IAT) sensor is a thermistor (a variable resistor that changes along with outside air temperature) in series with a fixed resistor in the PCM. The PCM applies 5 volts to the IAT sensor. The PCM monitors the voltage across the IAT sensor and converts it into a temperature reading. When the outside air temperature is cold the IAT sensor resistance is high, and when the outside air temperature is warm the IAT sensor resistance is low. Therefore, when the air temperature is cold the PCM will receive a high voltage input, and when the air temperature is warm the PCM will receive a low voltage input. The signal from IAT sensor is used for injection time correction (Cold post start correction), ignition angle correction(Air temperature correction) and idle speed correction(Air-density correction).
DTC DESCRIPTION
If the IAT sensor output voltage does not change, the PCM determines that a fault exists and a DTC is stored.
DTC Detecting Condition:
DTC DETECTING CONDITION
Specification:
SPECIFICATION
Schematic Diagram:
SCHEMATIC DIAGRAM
MONITOR SCANTOOL DATA
1. Ignition "OFF"
2. Install Scantool and Ignition "ON" & Engine "ON "
3. Monitor Intake Air Temperature Sensor parameter on Current data.
Specification : (Error range is 2 - 3%)
4. Is the measured IATS parameter displayed within specification?
YES: Fault is intermittent caused by poor contact in the sensor's and/or PCM' s connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection,bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Go to "W/Harness Inspection" procedure.
TERMINAL & CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminals.
Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. 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. Check IATS
1. Ignition "OFF"
2. Disconnect IATS connector.
3. Measure resistance between terminal 5 and 3 of IAT connector (Component side).
Specification : (error range is 2 - 3 %.)
4. Is the measured resistance within specifications ?
YES: Go to "Check PCM" as below.
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 IATS and go to "Verification of Vehicle Repair" procedure.
2. Check PCM
1. Ignition "OFF"
2. Connect scantool and Ignition "ON" & Engine "OFF"
3. Select simulation function on scantool.
4. Simulate voltage at terminal "5" of IAT sensor signal connector.
5. Does the signal value of IAT sensor changes according to simulation voltage ?
YES: Thoroughly check connectors for looseness, poor connection, bending,corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Substitute with a known - good PCM and check for proper operation.
If the problem is corrected, replace PCM and 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. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code(DTC) which has been diagnosed.
2. Using a Scantool, Clear the DTCs.
3. Operate the vehicle within conditions noted in the freeze frame data or enable conditions.
4. Monitor that all readiness test have been verified as "Complete"
5. Are any DTCs present ?
YES: Go to the applicable troubleshooting procedure.
NO: System is performing to specification at this time.