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DTC P0112: Intake Air Temperature Circuit Low Input; DTC P0113: Intake Air Temperature Circuit High Input: Procedure

READ VALUE USING TECHSTREAM (INTAKE AIR TEMPERATURE)

Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Enter the following menus: Powertrain / Engine and ECT / Intake Air.

Read the value displayed on the Techstream.

OK

Same as actual intake air temperature.

Result

Result	Proceed to
-40°C (-40°F)	A
Higher than 128°C (262°F)	B
Same as actual intake air temperature	C

HINT:

If there is an open circuit, the Techstream indicates -40°C (-40°F).

If there is a short circuit, the Techstream indicates higher than 128°C (262°F).

B → See step 7

C → See step 4

A: Go to next step

READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN WIRE HARNESS)
1. Disconnect the mass air flow meter connector.
  
  Fig 1: Identifying (THA) And (E2) Of Mass Air Flow Meter Wire Harness Side Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Connect terminals 1 (THA) and 2 (E2) of the mass air flow meter wire harness side connector.
3. Connect the Techstream to the DLC3.
4. Turn the ignition switch to ON.
5. Turn the Techstream on.
6. Enter the following menus: Powertrain / Engine and ECT / Intake Air.
7. Read the value displayed on the Techstream.
  Standard value
  
  Higher than 128°C (262°F)
8. Reconnect the mass air flow meter connector.
NG → See step 3

OK → See step 5

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

Disconnect the mass air flow meter connector.
Disconnect the ECM connector.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
B2-1 (THA) - B29-87 (THA)	Always	Below 1 Ω
B2-2 (E2) - B29-88 (ETHA)	Always	Below 1 Ω

Reconnect the mass air flow meter connector.
Reconnect the ECM connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (MASS AIR FLOW METER - ECM)

OK → See step 6

CHECK FOR INTERMITTENT PROBLEMS. Refer to CHECK FOR INTERMITTENT PROBLEMS
REPLACE MASS AIR FLOW METER. Refer to REMOVAL
REPLACE ECM. Refer to REMOVAL
READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS)
1. Disconnect the mass air flow meter connector.
  
  Fig 2: Mass Airflow Meter Circuit Diagram
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Connect the Techstream to the DLC3.
3. Turn the ignition switch to ON.
4. Turn the Techstream on.
5. Enter the following menus: Powertrain / Engine and ECT / Intake Air.
6. Read the value displayed on the Techstream.
  Standard value
  
  -40°C (-40°F)
7. Reconnect the mass air flow meter connector.
NG → See step 8

OK → See step 9

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

Disconnect the mass air flow meter connector.
Disconnect the ECM connector.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
B2-1 (THA) or B29-87 (THA) - Body ground	Always	10 kΩ or higher

Reconnect the mass air flow meter connector.
Reconnect the ECM connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (MASS AIR FLOW METER - ECM)

OK → See step 10

REPLACE MASS AIR FLOW METER. Refer to REMOVAL
REPLACE ECM. Refer to REMOVAL