Toyota Avalon (XX50) 2019-2022 Service & Repair Manual: Control Module Internal Temperature Sensor/Intake Air Temperature Sensor Signal Compare Failure (P111C62)

DESCRIPTION

The engine has an ECM internal temperature sensor and intake air temperature sensor.

The resistance of a thermistor within the ECM internal temperature sensor and intake air temperature sensor increases as the temperature decreases and decreases as the temperature increases.

The voltage monitored by the ECM changes in accordance with the change in the resistance of the thermistor.

The ECM performs control based on these voltages.

HINT:

• Waiting is required to prevent the temperature of the engine from affecting the readings. If the engine has been operated recently, it is not possible to accurately compare the readings.
• For diagnosis, in order to duplicate the detection conditions of the DTC, it is necessary to park the vehicle for 7 hours. Parking the vehicle for 7 hours ensures that the actual temperature of the ECM internal temperature and intake air temperature (for mass airflow meter sub-assembly) are very similar. When the vehicle has been parked for less than 7 hours, differences in the readings may exist, but this does not necessarily indicate a fault.

MONITOR DESCRIPTION

6, 6.5 and 7 hours after the engine has stopped, the ECM monitors the voltage of the ECM internal temperature sensor and intake air temperature sensor.

If the difference between the readings of the ECM internal temperature and intake air temperature is more than 20°C (36°F), the ECM determines that there is a malfunction in the ECM internal temperature sensor circuit or intake air temperature sensor circuit and stores a DTC and illuminates the MIL.

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

CONFIRMATION DRIVING PATTERN

HINT:

• After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

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• When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.

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1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Turn the Techstream on.
4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
5. Turn the power switch off.
6. With the engine stopped, leave the vehicle as is for 7.5 hours or more [A].
7. Turn the power switch on (IG).
8. Turn the Techstream on.
9. Wait 1 seconds [B].
10. Enter the following menus: Powertrain / Engine / Trouble Codes [C].
11. Read the pending DTCs.

    HINT:

    • If a pending DTC is output, the system is malfunctioning.
    • If a pending DTC is not output, perform the following procedure.
12. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
13. Input the DTC: P111C62.
14. Check the DTC judgment result.

    Techstream 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

    HINT:

    • If the judgment result is NORMAL, the system is normal.
    • If the judgment result is ABNORMAL, the system is malfunctioning.
    • If the judgment result is INCOMPLETE, perform steps [A] through [C] again.
    • [A] to [C]: Normal judgment procedure.

      The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

    • When clearing the permanent DTCs, do not disconnect the cable from the auxiliary battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.

CAUTION / NOTICE / HINT

NOTICE:

• Vehicle Control History may be stored in the hybrid vehicle control ECU assembly if the engine is malfunctioning. Certain vehicle condition information is recorded when Vehicle Control History is stored. Reading the vehicle conditions recorded in both the Freeze Frame Data and Vehicle Control History can be useful for troubleshooting.

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  (Select Powertrain in Health Check and then check the time stamp data.)

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• If any "Engine Malfunction" Vehicle Control History item has been stored in the hybrid vehicle control ECU assembly, make sure to clear it. However, as all Vehicle Control History items are cleared simultaneously, if any Vehicle Control History items other than "Engine Malfunction" are stored, make sure to perform any troubleshooting for them before clearing Vehicle Control History.

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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 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.

PROCEDURE

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine / Trouble Codes.

(e) Read the DTCs and record the Freeze Frame Data.

HINT:

If any DTCs other than P111C62 are output, troubleshoot those DTCs first.

B

GO TO DTC CHART

A

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream on.

(d) Using the Techstream, read the values displayed in the Freeze Frame Data recorded in step 1.

(e) Read the value displayed on the Techstream.

Standard:

Difference between the Intake Air Temperature and the Ambient Temperature is within 15°C (27°F).

HINT:

• When the engine is cold, the value of the intake air temperature, ECM internal temperature and ambient temperature should be approximately the same.
• Perform "Inspection After Repair" after replacing the mass air flow meter sub-assembly.

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OK

REPLACE ECM

NG

REPLACE MASS AIR FLOW METER SUB-ASSEMBLY