1A
DTC P0111: Intake Air Temperature Circuit Range / Performance
Wiring Diagram
1. MAF and IAT sensor 2. ECM 3. To other sensors 4. From main relay
DTC Detecting Condition and Trouble Area
DTC detecting condition Trouble area
Difference of maximum IAT minus minimum IAT is less than 0.3 °C (32.5 °F) while ECT is over 70 °C (158 °F) after 10 min from cold engine start (ECT is lower than 30 °C (86 °F) at engine start).
(2 driving cycle detection logic)
• High resistance in the circuit
• MAF and IAT sensor
• ECM
DTC Confirmation Procedure
NOTE:
Check to make sure that the following conditions are satisfied when using this “DTC Confirmation Procedure”.
• Intake air temperature at engine start: –10 °C (14 °F) to 80 °C (176 °F)
• Intake air temperature: –10 °C (14 °F) to 70 °C (158 °F)
• Engine coolant temperature at engine start: less than 30 °C (86 °F)
• Engine coolant temperature: 70 °C (158 °F) to 150 °C (302 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch, clear DTC using scan tool.
3) Start engine and warm up to normal operating temperature. (ECT approx. 70 – 205 °C, 158 – 401 °F)
4) Run engine at idle speed for 10 min. or more.
5) Check DTC and pending DTC.
DTC Troubleshooting
Step Action YES NO
1
Was “Engine and Emission Control System Check” performed?
Go to Step 2.
Go to Engine and Emission Control System Check:M13A with VVT .
2
IAT sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned OFF.
2) Turn ignition switch to ON position.
3) Check intake air temp. displayed on scan tool.
Is –40 °C (–40 °F) or 119 °C (246 °F) indicated?
Go to Step 3.
Intermittent trouble. Check for intermittent referring to Intermittent and Poor Connection Inspection .
3
Wire harness check
1) Disconnect MAF and IAT sensor connector (1) with ignition switch turned OFF.
2) Check for proper connection to MAF and IAT sensor connector (1) at “LT GRN/BLK” and “BLK/BLU” wire terminals.
3) If OK, then with ignition switch turned ON.
Is voltage applied to “LT GRN/BLK” wire terminal about 4 – 6 V?
Go to Step 8.
Go to Step 4.
4
ECM voltage check
1) Turn OFF ignition switch.
2) Check for proper connection of ECM connector at “E119-17” terminal.
3) If OK, then turn ON ignition switch, measure voltage between “E119-17” terminal of ECM connector and vehicle body ground.
Is voltage about 4 – 6 V at terminal?
Open wire in “LT GRN/BLK” circuit.
If wire and connection are OK, go to Step 5.
Go to Step 5.
5
Wire circuit check
1) Disconnect connectors from ECM with ignition switch turned OFF.
2) Measure resistance between “LT GRN/BLK” wire terminal of MAF and IAT sensor connector and vehicle body ground.
Is resistance infinity?
Go to Step 6.
“LT GRN/BLK” wire shorted to ground or other circuits.
If wire are OK, substitute a known-good ECM and recheck.
6
Wire circuit check
1) Turn ignition switch to ON position.
2) Measure voltage between “LT GRN/BLK” wire terminal of MAF and IAT sensor connector and body ground.
Is voltage about 0 V?
Go to Step 7.
“LT GRN/BLK” wire shorted to other circuits.
If wire are OK, substitute a known-good ECM and recheck.
7
Wire circuit check
1) Measure resistance between “E119-17” terminal of ECM connector and “LT GRN/BLK” wire terminal of MAF and IAT sensor connector with ignition switch turned OFF.
Is resistance below 3 Ω?
Go to Step 8.
High resistance wire in “LT GRN/BLK” circuit.
8
Ground circuit check
1) Connect connectors to ECM.
2) Check for proper connection of MAF and IAT sensor connector at “BLK/BLU” wire terminal.
3) Measure resistance between “BLK/BLU” wire terminal of MAF and IAT sensor connector and vehicle body ground with ignition switch turned OFF.
Is resistance below 5 Ω?
Go to Step 10.
Go to Step 9.
9
Ground circuit check
1) Measure resistance between “E119-28” terminal of ECM connector and vehicle body ground.
Is resistance below 3 Ω?
Open or high resistance wire in “BLK/BLU” circuit.
Poor “E119-28” connection.
Faulty ECM ground circuit.
If circuit are OK, substitute a known-good ECM and recheck.
10
IAT sensor check
1) Check IAT sensor according to Mass Air Flow (MAF) and Intake Air Temperature (IAT) Sensor On-Vehicle Inspection (With VVT):M13A .
Is it in good condition?
Substitute a known-good ECM and recheck.
Replace MAF and IAT sensor.
NOTE:
Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.