| DTC Code | DTC Name |
|---|---|
| P0112 | Intake Air Temperature Circuit Low Input |
| P0113 | Intake Air Temperature Circuit High Input |
DESCRIPTION
The intake air temperature sensor is built into the Mass Air Flow (MAF) meter and senses 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 greater 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 in 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 changes in the intake air temperature, the potential at terminal THA also changes. Based on this signal, the ECM increases the fuel injection volume to improve drivability with a cold engine.
Tech Tips
When the intake air temperature sensor output is outside the normal range, the ECM determines that this is a malfunction.
| DTC Detection Drive Pattern | DTC Detection Condition | Trouble Area |
|---|---|---|
| Engine idles for approximately 15 seconds | Intake air temperature sensor output is more than 140°C (284°F). (2 trip detection logic) |
|
| DTC Detection Drive Pattern | DTC Detection Condition | Trouble Area |
|---|---|---|
| Engine idles for approximately 15 seconds | Intake air temperature sensor output is less than -40°C (-40°F). (2 trip detection logic) |
|
| DTC No. | Data List |
|---|---|
| P0112 | Intake Air |
| P0113 |
Tech Tips
If DTC P0112 or P0113 is stored, the following symptoms may appear:
Misfire
Combustion noise
Black smoke
White smoke
Lack of power
When DTC P0112 or P0113 is stored, 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) | Short circuit |
WIRING DIAGRAM
| *a | INTAKE AIR TEMPERATURE SENSOR (Built into Mass Air Flow Meter) |
CAUTION / NOTICE / HINT
Note
When replacing the ECM, the ECM needs Registration and Initialization Click here.
Tech Tips
When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the intelligent tester. Then after installing the new ECM, perform all of the initialization/registrations for the "Learning Values Write" function by following the instructions shown on the tester display.
Read freeze frame data using the intelligent tester. 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.
PROCEDURE
READ VALUE USING INTELLIGENT TESTER (INTAKE AIR)
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air.
Read the value.
| OK |
|---|
| Same as actual intake air temperature. |
| Result | Proceed to |
|---|---|
| -40°C (-40°F) | A |
| 140°C (284°F) or higher | B |
| Same as actual intake air temperature | C |
Tech Tips
If there is an open circuit, the intelligent tester indicates -40°C (-40°F).
If there is a short circuit, the intelligent tester indicates 140°C (284°F) or higher.
| B |
|
READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN WIRE HARNESS) Click here |
| C |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here |
| A |
|
READ VALUE USING INTELLIGENT TESTER (CHECK FOR OPEN IN WIRE HARNESS)
| *1 | Mass Air Flow Meter |
| *a | Front view of wire harness connector (to Mass Air Flow Meter) |
Disconnect the mass air flow meter connector.
Connect terminals THA and E2 of the mass air flow meter wire harness side connector.
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air.
Read the value.
| Standard |
|---|
| 140°C (284°F) or higher |
Reconnect the mass air flow meter connector.
| OK |
|
CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE MASS AIR FLOW METER Click here |
| NG |
|
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 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
Reconnect the mass air flow meter connector.
Reconnect the ECM connector.
| OK |
|
CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR Click here |
READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN WIRE HARNESS)
Disconnect the mass air flow meter connector.
| *1 | Mass Air Flow Meter |
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the tester on.
Reconnect the mass air flow meter connector.
Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air.
Read the value.
| Standard |
|---|
| -40°C (-40°F) |
Reconnect the mass air flow meter connector.
| OK |
|
REPLACE MASS AIR FLOW METER Click here |
| NG |
|
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 | ||||||
|---|---|---|---|---|---|---|
|
Reconnect the mass air flow meter connector.
Reconnect the ECM connector.
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR Click here |
| OK |
|
REPLACE ECM
Replace the ECM Click here.
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here |
CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE MASS AIR FLOW METER
Replace the mass air flow meter Click here.
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here |
REPAIR OR REPLACE HARNESS OR CONNECTOR
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here |
CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM
Replace the ECM Click here.
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here |
REPLACE MASS AIR FLOW METER
Replace the mass air flow meter Click here.
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
Connect the intelligent tester to the DLC3.
Clear the DTCs Click here.
Start the engine.
Allow the engine to idle for 15 seconds or more.
Enter the following menus: Powertrain / Engine and ECT / DTC.
Confirm that the DTC is not output again.
| NEXT |
|
END |