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:
  1. Blower switch is ON
  2. Outside temperature is 10°C (50°F) or less
  3. Coolant temperature is less than 55 (131°F )
Heater function is not effective
  1. Blower switch is turned off
  2. Coolant temperature is 55°C (131°F) or more:
During heater operation
Cooling function:
All of the following conditions have been met:
  1. Blower switch is ON
  2. A/C switch is on
  3. Outside temperature is 25°C (77°F) or more
  4. 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
  1. Evaporator temperature is 15°C (59°F) or less
  2. Blower switch is turned off
  3. 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


A217715E01


INSPECTION PROCEDURE

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

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the tester on.

  1. Enter the following menus: Powertrain / Stop and Start / Data List / A/C Outlet Temp.

  1. 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.

    HINT:
    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
Go to step 2
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.

  1. 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

  1. 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.

  1. 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

  1. 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)