STOP AND START SYSTEM Cooler Thermistor Circuit

DESCRIPTION

Stop and Start system control may be prohibited due to air conditioning system operation conditions. The prohibition conditions are shown in the table below.

System Prohibition Control due to Air Conditioning Operation Conditions
Prohibition Condition Effect without Restart Restoration Condition Prohibition Condition Check Timing

Heater:

All of the following conditions have been met:


  • Blower switch is ON

  • Outside temperature is 10°C (50°F) or less

  • Coolant temperature is less than 55 (131°F )

 Heater function is not effective

  • Blower switch is turned off

  • Coolant temperature is 55°C (131°F) or more:

 During heater operation

Cooling function:

All of the following conditions have been met:


  • Blower switch is ON

  • A/C switch is on

  • Outside temperature is 25°C (77°F) or more

  • Evaporator temperature is 15°C (59°F) or more (Once the temperature drops below 15°C (59°F) after the ignition switch is turned to ON, Stop and Start system control will be restored)

 Cooling function is not effective

Any of the following conditions have been met


  • Evaporator temperature is 15°C (59°F) or less

  • Blower switch is turned off

  • A/C is turned off

 While A/C (cooling function) is on

Defogger:


  1. Outside temperature is 3°C (37.4°F) or less, and A/C switch and blower switch are on

  2. DEF switch is on (only for auto A/C)

  3. A subsequent idle stop operation is prohibited for 40 to 90 seconds after an idle stop is performed with an outside temperature of 3 to 8°C (37.4 to 46.4°F)

 Windows are easily fogged

The corresponding condition has been met:


  1. A/C or blower switch is turned off

  2. A/C or blower switch is turned off

  3. 40 to 90 seconds have elapsed after idle stop, or A/C or blower switch is turned off

 While A/C (cooling function for defogger) is on

WIRING DIAGRAM

A0117Y3E01

INSPECTION PROCEDURE

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (A/C OUTLET TEMP)


    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 / Stop and Start / Data List / A/C Outlet Temp.

    5. Read the value when the A/C temperature switch is operated (HOT to COOL).

      OK
      Tester display value changes when the A/C switch is operated.

      Tech Tips

      The A/C Outlet Temp item in the Data List indicates the A/C blower temperature. Leaving the vehicle for an entire day allows the A/C Outlet Temperature value to equal the ambient temperature. While the ambient temperature is indicated in the Data List, check for changes in the outlet temperature by hand. If temperature changes cannot be felt, inspect the air conditioning system.


    NG

    INSPECT COOLER THERMISTOR Click here

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

  2. INSPECT COOLER THERMISTOR


    1. Inspect the cooler thermistor Click here.


    NG

    REPLACE COOLER THERMISTOR Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - COOLER THERMISTOR)


    1. Disconnect the cooler thermistor connector and engine stop and start ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D79-24 (E2) - D77-2 (SG) Always Below 1 Ω
      D78-10 (TFAL) - D77-1 (TFAR) Always Below 1 Ω
      D79-24(E2) or D77-2(SG) - Body ground Always 10 kΩ or higher
      D78-10(TFAL) or D77-1(TFAR) - Body ground Always 10 kΩ or higher

    3. Reconnect the cooler thermistor connector and engine stop and start ECU connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - BODY GROUND)


    1. Disconnect the engine stop and start ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D78-1 (EC) - Body ground Always Below 1 Ω
      D78-6 (E1) - Body ground Always Below 1 Ω

    3. Reconnect the engine stop and start ECU connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here