Dtc P0112 Intake Air Temperature Circuit Low Input

Engine Hybrid System. Corolla. Zre142 Aze141
2Az-Fe Engine Control. Corolla. Zre142 Aze141

DESCRIPTION

MONITOR DESCRIPTION

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

CONFIRMATION DRIVING PATTERN

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING TECHSTREAM (INTAKE AIR TEMPERATURE)

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

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

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

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

DTC P0112 Intake Air Temperature Circuit Low Input

DTC P0113 Intake Air Temperature Circuit High Input


DESCRIPTION

Corolla. Zre142 Aze141.2Az-Fe Engine Control.Sfi System. Dtc P0112 Intake Air Temperature Circuit Low Input
  1. The intake air temperature sensor, mounted on the mass air flow meter, monitors the intake air temperature. The intake air temperature sensor has a built-in thermistor with a resistance that varies according to the temperature of the intake air. When the intake air temperature becomes low, the resistance of the thermistor increases. When the temperature becomes high, the resistance drops. These variations in resistance are transmitted to the ECM as voltage changes (see Fig. 1).
  2. The intake air temperature sensor is powered by a 5 V supply from the THA terminal of the ECM, via resistor R which is located inside the ECM.
  3. Resistor R and the intake air temperature sensor are connected in series. When the resistance value of the intake air temperature sensor changes, according to changes in the intake air temperature, the voltage at terminal THA also varies. Based on this signal, the ECM increases the fuel injection volume when the engine is cold to improve driveability.
    HINT:
    When any of DTCs P0112 and P0113 are stored, the ECM enters fail-safe mode. During fail-safe mode, the intake air temperature is estimated to be 20°C (68°F) by the ECM. Fail-safe mode continues until a pass condition is detected.

DTC No.
DTC Detection Condition
Trouble Area
P0112
Short in intake air temperature sensor circuit 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)
  3. ECM
P0113
Open in intake air temperature sensor circuit 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)
  3. ECM
HINT:
When any of these DTCs are set, check the intake air temperature by entering the following menus: Powertrain / Engine and ECT / Primary / Intake Air.

Temperature Displayed
Malfunction
-40°C (-40°F)
Open circuit
More than 128°C (262°F)
Short circuit

MONITOR DESCRIPTION

The ECM monitors the sensor voltage and uses this value to calculate the intake air temperature. When the sensor output voltage deviates from the normal operating range, the ECM interprets this as a malfunction in the intake air temperature sensor circuit and stores a DTC.
Example:
If the sensor output voltage is more than 4.91 V for 0.5 seconds or more, the ECM determines that there is an open in the intake air temperature sensor circuit, and sets DTC P0113. Conversely, if the output voltage is less than 0.18 V for 0.5 seconds or more, the ECM determines that there is a short in the sensor circuit, and stores DTC P0112.

MONITOR STRATEGY


Related DTCs
P0112: Intake air temperature sensor range check (Low voltage)
P0113: Intake air temperature sensor range check (High voltage)
Required Sensors/Components (Main)
Intake air temperature sensor
Required Sensors/Components (Related)
-
Frequency of Operation
Continuous
Duration
0.5 seconds
MIL Operation
Immediate
Sequence of Operation
None

TYPICAL ENABLING CONDITIONS


Monitor runs whenever following DTCs are not present
None
Battery voltage
8 V or more
Ignition switch
ON
Starter
Off

TYPICAL MALFUNCTION THRESHOLDS


P0112
Intake air temperature sensor voltage [Intake air temperature]
Less than 0.18 V [More than 128°C (262°F)]

P0113
Intake air temperature sensor voltage [Intake air temperature]
More than 4.91 V [Less than -55°C (-67°F)]

COMPONENT OPERATING RANGE


Intake air temperature sensor voltage [Intake air temperature]
0.18 to 4.91 V [-55 to 128°C (-67 to 262°F)]

CONFIRMATION DRIVING PATTERN

  1. Connect the Techstream to the DLC3.
  2. Turn the ignition switch to ON and turn the Techstream on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the ignition switch off and wait for at least 30 seconds.
  5. Turn the ignition switch to ON and turn the Techstream on.
  6. Wait 0.5 seconds or more.
  7. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
  8. Read the pending DTCs.
    HINT:
    1. If a pending DTC is output, the system is malfunctioning.
    2. If a pending DTC is not output, perform the following procedure.
  9. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
  10. Input the DTC: P0112 or P0113.
  11. Check the DTC judgment result.

    Techstream Display
    		Description
    NORMAL
    1. DTC judgment completed
    2. System normal
    ABNORMAL
    1. DTC judgment completed
    2. System abnormal
    INCOMPLETE
    1. DTC judgment not completed
    2. Perform driving pattern after confirming DTC enabling conditions
    N/A
    1. Unable to perform DTC judgment
    2. Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit
    HINT:
    1. If the judgment result shows NORMAL, the system is normal.
    2. If the judgment result shows ABNORMAL, the system has a malfunction.
  12. If the judgment result is INCOMPLETE or N/A and no pending DTC is output, perform a universal trip and check for permanent DTCs (COROLLA_ZRE142 RM000000PDK0ZBX.html).
    HINT:
    1. If a permanent DTC is output, the system is malfunctioning.
    2. If no permanent DTC is output, the system is normal.

WIRING DIAGRAM


Corolla. Zre142 Aze141.2Az-Fe Engine Control.Sfi System. Dtc P0112 Intake Air Temperature Circuit Low Input


INSPECTION PROCEDURE

HINT:
Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.
1.READ VALUE USING TECHSTREAM (INTAKE AIR TEMPERATURE)

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

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

  1. Read the value displayed on the Techstream.

    OK:
    Same as actual intake air temperature.

    Result:

    Result
    		Proceed to
    -40°C (-40°F)
    		A
    More than 128°C (262°F)
    		B
    Same as actual intake air temperature
    		C
    HINT:
    1. If there is an open circuit, the Techstream indicates -40°C (-40°F).
    1. If there is a short circuit, the Techstream indicates more than 128°C (262°F).


B
Go to step 4

C
CHECK FOR INTERMITTENT PROBLEMS (COROLLA_ZRE142 RM000000PDQ0VNX.html)
A


2.READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN WIRE HARNESS)
Corolla. Zre142 Aze141.2Az-Fe Engine Control.Sfi System. Dtc P0112 Intake Air Temperature Circuit Low Input

  1. Disconnect the mass air flow meter connector.

  1. Connect terminals 1 (THA) and 2 (E2) of the mass air flow meter wire harness side connector.

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

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

  1. Read the value displayed on the Techstream.

    Standard Value:
    More than 128°C (262°F)

  1. Reconnect the mass air flow meter connector.



NG
Go to step 3
OK

REPLACE MASS AIR FLOW METER (COROLLA_ZRE142 RM0000017TX03AX.html)

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

  1. Disconnect the mass air flow meter 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
    B2-1 (THA) - B31-65 (THA)
    		Always
    		Below 1 Ω
    B2-2 (E2) - B31-88 (ETHA)
    		Always
    		Below 1 Ω

  1. Reconnect the mass air flow meter connector.

  1. Reconnect the ECM connector.



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

REPLACE ECM (COROLLA_ZRE142 RM000002WT402ZX.html)

4.READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS)
Corolla. Zre142 Aze141.2Az-Fe Engine Control.Sfi System. Dtc P0112 Intake Air Temperature Circuit Low Input

  1. Disconnect the mass air flow meter connector.

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

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

  1. Read the value displayed on the Techstream.

    Standard Value:
    -40°C (-40°F)

  1. Reconnect the mass air flow meter connector.



NG
Go to step 5
OK

REPLACE MASS AIR FLOW METER (COROLLA_ZRE142 RM0000017TX03AX.html)

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

  1. Disconnect the mass air flow meter 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
    B2-1 (THA) or B31-65 (THA) - Body ground
    		Always
    		10 kΩ or higher

  1. Reconnect the mass air flow meter connector.

  1. Reconnect the ECM connector.



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

REPLACE ECM (COROLLA_ZRE142 RM000002WT402ZX.html)