Dtc P0112 Intake Air Temperature Circuit Low Input


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING GTS (INTAKE AIR TEMPERATURE)

READ VALUE USING GTS (CHECK FOR OPEN IN WIRE HARNESS)

CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE MASS AIR FLOW METER. SUB-ASSEMBLY

CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - ECM)

CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM.

READ VALUE USING GTS (CHECK FOR SHORT IN WIRE HARNESS)

REPLACE MASS AIR FLOW METER SUB-ASSEMBLY

CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - ECM)

REPLACE ECM

REPAIR OR REPLACE HARNESS OR CONNECTOR

CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

DTC P0112 Intake Air Temperature Circuit Low Input

DTC P0113 Intake Air Temperature Circuit High Input


DESCRIPTION

The intake air temperature sensor is built into the mass air flow meter sub-assembly and detects the intake air temperature.
A thermistor built into the sensor changes its resistance value according to the intake air temperature.
The lower the intake air temperature, the higher the thermistor resistance value. The higher the intake air temperature, the lower the thermistor resistance value (See Fig. 1).
The intake air temperature sensor is connected to the ECM.
The 5 V power source voltage from the ECM is applied to the intake air temperature sensor from terminal THA via resistor R.
Resistor R and the intake air temperature sensor are connected in series. When the resistance value of the intake air temperature sensor changes in accordance with the intake air temperature, the voltage at terminal THA also changes. Based on this signal, the ECM increases the fuel injection volume to improve driveability with a cold engine.
Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.1Gd-Ftv Engine Control.Ecd System. Dtc P0112 Intake Air Temperature Circuit Low Input

P0112
DTC Detection Drive Pattern
DTC Detection Condition
Trouble Area
Engine switch on (IG) for 0.5 seconds
Short in the intake air temperature sensor for 0.5 seconds (1 trip detection logic).
  1. Short in intake air temperature sensor circuit
  2. Intake air temperature sensor (built into mass air flow meter sub-assembly)
  3. ECM

P0113
DTC Detection Drive Pattern
DTC Detection Condition
Trouble Area
Engine switch on (IG) for 0.5 seconds
Open in the intake air temperature sensor for 0.5 seconds (1 trip detection logic).
  1. Open in intake air temperature sensor circuit
  2. Intake air temperature sensor (built into mass air flow meter sub-assembly)
  3. ECM

Related Data List
DTC No.
Data List
P0112
P0113
Intake Air
HINT:
  1. If DTC P0112 and/or P0113 is stored, the following symptoms may appear:
    1. Misfire
    2. Combustion noise
    3. Black smoke
    4. White smoke
    5. Lack of power
  2. When DTC P0112 or P0113 is stored, check the intake air temperature by entering the following menus: Powertrain / Engine and ECT / Data List / Intake Air.

    Reference
    GTS Displayed
    		Malfunction
    -40°C (-40°F)
    		Open circuit
    140°C (284°F) or higher
    		Short circuit

WIRING DIAGRAM

Refer to DTC P0100 (LandCruiser RM00000187J09GX_02.html).

INSPECTION PROCEDURE

NOTICE:
After replacing the ECM, the new ECM needs registration (LandCruiser RM0000012XK0AUX.html) and initialization (LandCruiser RM000000TIN08HX.html).
HINT:
Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.
1.READ VALUE USING GTS (INTAKE AIR TEMPERATURE)

  1. Connect the GTS to the DLC3.

  1. Turn the engine switch on (IG) and turn the GTS on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air.

  1. Read the value.

    OK:
    Same as actual intake air temperature

    Result
    Result
    		Proceed to
    -40°C (-40°F)
    		A
    140°C (284°F) or higher
    		B
    OK (same as actual intake air temperature)
    		C
    HINT:
    1. If there is an open circuit, the GTS indicates -40°C (-40°F).
    2. If there is a short circuit, the GTS indicates 140°C (284°F) or higher.


B
Go to step 6

C
Go to step 11
A


2.READ VALUE USING GTS (CHECK FOR OPEN IN WIRE HARNESS)


  1. Disconnect the mass air flow meter sub-assembly connector.


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.1Gd-Ftv Engine Control.Ecd System. Dtc P0112 Intake Air Temperature Circuit Low Input

  1. Connect terminals 4 (THA) and 2 (E2G) of the mass air flow meter sub-assembly wire harness side connector.

  1. Connect the GTS to the DLC3.

  1. Turn the engine switch on (IG) and turn the GTS on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air.

  1. Read the value.

    OK:
    140°C (284°F) or higher
    Text in Illustration
    *1
    		Mass air flow meter sub-assembly
    *2
    		ECM
    *a
    		Front view of wire harness connector
    (to Mass Air Flow Meter Sub-assembly)

  1. Reconnect the mass air flow meter sub-assembly connector.



NG
Go to step 4
OK


3.CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE MASS AIR FLOW METER. SUB-ASSEMBLY

  1. Replace the mass air flow meter sub-assembly (LandCruiser RM000000VHD05PX.html).



NEXT
Go to step 11

4.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - ECM)

  1. Disconnect the mass air flow meter sub-assembly connector.

  1. Disconnect the ECM connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:

    Tester Connection
    		Condition
    		Specified Condition
    C33-4 (THA) - C150-32 (THA)
    		Always
    		Below 1 Ω
    C33-2 (E2G) - C150-24 (EVG)
    		Always
    		Below 1 Ω

  1. Reconnect the mass air flow meter sub-assembly connector.

  1. Reconnect the ECM connector.



NG
Go to step 10
OK


5.CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM.

  1. Replace the ECM (LandCruiser RM0000013Z002DX.html).



NEXT
Go to step 11

6.READ VALUE USING GTS (CHECK FOR SHORT IN WIRE HARNESS)


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.1Gd-Ftv Engine Control.Ecd System. Dtc P0112 Intake Air Temperature Circuit Low Input

  1. Disconnect the mass air flow meter sub-assembly connector.

  1. Connect the GTS to the DLC3.

  1. Turn the engine switch on (IG) and turn the GTS on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air.

  1. Read the value.

    OK:
    -40°C (-40°F)
    Text in Illustration
    *1
    		Mass Air Flow Meter Sub-assembly
    *2
    		ECM

  1. Reconnect the mass air flow meter sub-assembly connector.



NG
Go to step 8
OK


7.REPLACE MASS AIR FLOW METER SUB-ASSEMBLY

  1. Replace the mass air flow meter sub-assembly (LandCruiser RM0000013Z002DX.html).



NEXT
Go to step 11

8.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - ECM)

  1. Disconnect the mass air flow meter sub-assembly connector.

  1. Disconnect the ECM connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:

    Tester Connection
    		Condition
    		Specified Condition
    C33-4 (THA) or C150-32 (THA) - Body ground and other terminals
    		Always
    		10 kΩ or higher

  1. Reconnect the mass air flow meter sub-assembly connector.

  1. Reconnect the ECM connector.



NG
Go to step 10
OK


9.REPLACE ECM

  1. Replace the ECM (LandCruiser RM0000013Z002DX.html).



NEXT
Go to step 11

10.REPAIR OR REPLACE HARNESS OR CONNECTOR

  1. Repair or replace the harness or connector.



NEXT
Go to step 11

11.CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

  1. Connect the GTS to the DLC3.

  1. Clear the DTCs (LandCruiser RM000000PDK1E5X.html).

  1. Turn the engine switch on (IG) for 1 second.

  1. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

  1. Confirm that the DTC is not output again.


NEXT

END