Dtc P0110 Intake Air Temperature Circuit Malfunction

DESCRIPTION

MONITOR DESCRIPTION

CONFIRMATION DRIVING PATTERN

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING INTELLIGENT TESTER (INTAKE AIR TEMPERATURE)

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

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

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

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

DESCRIPTION

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 is low, the resistance of the thermistor increases. When the temperature is 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.
   
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 P0110, 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.

HINT:

When any of these DTCs are output, check the intake air temperature by entering the following menus: Powertrain / Engine and ECT / Data List / Intake Air.

MONITOR DESCRIPTION

CONFIRMATION DRIVING PATTERN

1. Connect the intelligent tester to the DLC3.
   
2. Turn the ignition switch to ON and turn the tester 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 tester on.
   
6. Wait 5 seconds or more.
   
7. Enter the following menus: Powertrain / Engine and ECT / DTC.
   
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: P0110, P0112 or P0113.
    
11. Check the DTC judgment result.
    
    

    Tester Display	Description
    NORMAL	DTC judgment completed System normal
    ABNORMAL	DTC judgment completed System abnormal
    INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions
    N/A	Unable to perform DTC judgment 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.
       
    3. If the judgment result shows INCOMPLETE or N/A, perform the Confirmation Driving Pattern and the DTC judgment result again.
       

WIRING DIAGRAM

INSPECTION PROCEDURE

HINT:

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, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

1. Connect the intelligent tester to the DLC3.
   

2. Turn the ignition switch to ON.
   

3. Turn the tester on.
   

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

5. Read the value displayed on the tester.
   

   Result

   Result	Proceed to
   -40°C (-40°F)	A
   140°C (284°F) or higher	B
   Same as actual intake air temperature	C

   HINT:

   1. If there is an open circuit, the intelligent tester indicates -40°C (-40°F).
      
   1. If there is a short circuit, the intelligent tester indicates 140°C (284°F) or higher.
      

1. Disconnect the mass air flow meter connector.
   

2. Connect terminals 4 (THA) and 5 (E2) of the mass air flow meter wire harness side connector.
   

3. Connect the intelligent tester to the DLC3.
   

4. Turn the ignition switch to ON.
   

5. Turn the tester on.
   

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

7. Read the value displayed on the tester.
   

   Standard value:

   140°C (284°F) or higher
   

   Text in Illustration

   *1	Mass Air Flow Meter
   *2	ECM
   *a	Front view of wire harness connector (to Mass Air Flow Meter)

1. Disconnect the mass air flow meter connector.
   

2. Disconnect the ECM connector.
   

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

   Standard Resistance:

   
   

   Tester Connection	Condition	Specified Condition
   C36-4 (THA) - C129-22 (THA)	Always	Below 1 Ω
   C36-5 (E2) - C129-28 (E2)	Always	Below 1 Ω

1. Disconnect the mass air flow meter connector.
   

2. Connect the intelligent tester to the DLC3.
   

3. Turn the ignition switch to ON.
   

4. Turn the tester on.
   

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

6. Read the value displayed on the tester.
   

   Standard value:

   -40°C (-40°F)
   

   Text in Illustration

   *1	Mass Air Flow Meter
   *2	ECM

1. Disconnect the mass air flow meter connector.
   

2. Disconnect the ECM connector.
   

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

   Standard Resistance:

   
   

   Tester Connection	Condition	Specified Condition
   C36-4 (THA) or C129-22 (THA) - Body ground	Always	10 kΩ or higher