Dtc P0110 Intake Air Temperature Circuit


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING INTELLIGENT TESTER (INTAKE AIR TEMPERATURE)

READ VALUE USING INTELLIGENT TESTER (CHECK FOR OPEN IN WIRE HARNESS)

READ VALUE USING INTELLIGENT TESTER (CHECK FOR OPEN IN ECM)

READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN WIRE HARNESS)

READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN ECM)

DTC P0110 Intake Air Temperature Circuit

DTC P0112 Intake Air Temperature Circuit Low Input

DTC P0113 Intake Air Temperature Circuit High Input


DESCRIPTION

The Intake Air Temperature (IAT) sensor, built into the Mass Air Flow (MAF) meter, monitors the IAT. The IAT sensor has a thermistor that varies its resistance depending on the temperature of the intake air. When the air temperature is low, the resistance in the thermistor increases. When the air temperature is high, the resistance decreases. The variations in resistance are communicated to the ECM as change in voltage (see Fig. 1). The IAT sensor is connected to the ECM. The 5 V power source voltage in the ECM is applied to the IAT sensor from terminal THA via resistor R.
The resistor R and the IAT sensor are connected in series. When the resistance value of the IAT sensor changes in accordance with changes in the IAT, the voltage at terminal THA also changes. Based on this signal, the ECM increases the fuel injection volume to improve the driveability during cold engine operation.
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.1Kd-Ftv Engine Control System.Ecd System. Dtc P0110 Intake Air Temperature Circuit
The Intake Air Temperature (IAT) sensor, mounted on the air cleaner hose, monitors the IAT.
The IAT sensor has a thermistor that varies its resistance depending on the temperature of the intake air. When the air temperature is low, the resistance in the thermistor increases. When the temperature is high, the resistance decreases. The variations in resistance are communicated to the ECM as changes in voltage (see Fig. 1).
The IAT sensor is connected to the ECM (see below). The 5 V power source voltage in the ECM is applied to the IAT sensor from terminal THA via resistor R.
The resistor R and the IAT sensor are connected in series. When the resistance value of the IAT sensor changes in accordance with changes in the IAT, the voltage at terminal THA also changes. Based on this signal, the ECM increases the fuel injection volume to improve the driveability during cold engine operation.

DTC No.
DTC Detection Condition
Trouble Area
P0110
Open or short in IAT sensor circuit for 0.5 seconds (1 trip detection logic)
  1. Open or short in IAT sensor circuit
  2. IAT sensor (built into MAF meter)
  3. ECM
P0112
Short in IAT sensor circuit for 0.5 seconds (1 trip detection logic)
  1. Open or short in IAT sensor circuit
  2. IAT sensor (built into MAF meter)
  3. ECM
P0113
Open in IAT sensor circuit for 0.5 seconds (1 trip detection logic)
  1. Open or short in IAT sensor circuit
  2. IAT sensor (built into MAF meter)
  3. ECM

HINT:
When DTC P0110, P0112 or P0113 is detected, check the intake air temperature by entering the following menus on the intelligent tester: Powertrain / Engine and ECT / Data List / Intake Air.

Temperature Displayed
Malfunction
-40°C (-40°F)
Open circuit
140°C (284°F) or more
Short circuit

WIRING DIAGRAM


Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.1Kd-Ftv Engine Control System.Ecd System. Dtc P0110 Intake Air Temperature Circuit


INSPECTION PROCEDURE

HINT:
  1. If DTCs related to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.
  2. Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, and other data from the time the malfunction occurred.
NOTICE:
If the ECM is replaced, the new ECM needs initialization (Toyota Fortuner RM000000TIN04NX.html).
1.READ VALUE USING INTELLIGENT TESTER (INTAKE AIR TEMPERATURE)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch ON and turn the intelligent tester ON.

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

  1. Read the values.

    Result:
    Temperature Displayed
    		Proceed to
    -40°C (-40°F)
    		A
    140°C (284°F) or more
    		B
    Same as air temperature near to intake manifold
    		C
    HINT:
    1. If there is an open circuit, the intelligent tester indicates -40°C (-40°F).
    2. If there is a short circuit, the intelligent tester indicates 140°C (284°F) or more.


B
Go to step 4

C
CHECK FOR INTERMITTENT PROBLEMS
A


2.READ VALUE USING INTELLIGENT TESTER (CHECK FOR OPEN IN WIRE HARNESS)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.1Kd-Ftv Engine Control System.Ecd System. Dtc P0110 Intake Air Temperature Circuit

  1. Disconnect the A4 MAF meter connector.

  1. Connect terminals 4 and 5 of the MAF meter wire harness side connector.

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch ON and turn the intelligent tester ON.

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

  1. Read the values.

    OK:
    Temperature value is 140°C (284°F) or more


OK
CONFIRM GOOD CONNECTION AT SENSOR. IF OK, REPLACE MASS AIR FLOW METER
NG


3.READ VALUE USING INTELLIGENT TESTER (CHECK FOR OPEN IN ECM)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.1Kd-Ftv Engine Control System.Ecd System. Dtc P0110 Intake Air Temperature Circuit

  1. Disconnect the A4 MAF meter connector.

  1. Connect terminals THA and E2 of the E7 ECM connector.

    HINT:
    Before checking, perform a visual and contact pressure check on the ECM connector.

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch ON and turn the intelligent tester ON.

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

  1. Read the values.

    OK:
    Temperature value is 140°C (284°F) or more


OK
REPAIR OR REPLACE HARNESS AND CONNECTOR
NG

CONFIRM GOOD CONNECTION AT ECM. IF OK, REPLACE ECM

4.READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN WIRE HARNESS)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.1Kd-Ftv Engine Control System.Ecd System. Dtc P0110 Intake Air Temperature Circuit

  1. Disconnect the A4 MAF meter.

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch ON and turn the intelligent tester ON.

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

  1. Read the values.

    OK:
    Temperature value is -40°C (-40°F)


OK
REPLACE MASS AIR FLOW METER
NG


5.READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN ECM)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.1Kd-Ftv Engine Control System.Ecd System. Dtc P0110 Intake Air Temperature Circuit

  1. Disconnect the A4 MAF meter.

  1. Disconnect the E7 ECM connector.

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch ON and turn the intelligent tester ON.

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

  1. Read the values.

    OK:
    Temperature value is -40°C (-40°F)


OK
REPAIR OR REPLACE HARNESS AND CONNECTOR
NG

REPLACE ECM