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Cooling Fan Circuit [10/2018 - ]: Procedure

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  1. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE ENGINE COOLING FAN DUTY RATIO) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Active Test / Control the Engine Cooling Fan Duty Ratio.

      Powertrain > Engine > Active Test 

      Tester Display
      Control the Engine Cooling Fan Duty Ratio
    5. Check the operation of the cooling fans while operating them using the Techstream.

      OK

      Tester Operation Fan Operation
      30-100% Cooling fans operate
      0% Cooling fans stop
    6. Turn the power switch on (IG).

      Result

      Result Proceed to
      OK A
      NG (Cooling fan LH do not operate) B
      NG (Cooling fan RH do not operate) C
      NG (Cooling fan LH do not stop) D
      NG (Cooling fan RH do not stop) E

    Result: 

    A 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [10/2018 - ]  

    Result: 

    C 

    See step  6

    Result: 

    D 

    See step  10

    Result: 

    E 

    See step  11

    Result: 

    B 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR LH POWER SOURCE CIRCUIT) 
    1. Disconnect the A6 cooling fan motor LH connector.
    2. Measure the voltage according to the value(s) in the table below.
      GTY810608Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Cooling Fan Motor LH)

      Standard Voltage

      Tester Connection Condition Specified Condition
      A6-1 (+B1) - A6-2 (E1) Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR LH POWER SOURCE CIRCUIT) 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR LH - EFI-MAIN NO. 1 RELAY) 
    1. Disconnect the A6 cooling fan motor LH connector.
    2. Remove the EFI-MAIN NO. 1 relay from the No. 1 engine room relay block.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      A6-4 (IGS1) - 3 (EFI-MAIN NO. 1 relay) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A6-4 (IGS1) or 3 (EFI-MAIN NO. 1 relay) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR LH - EFI-MAIN NO. 1 RELAY) 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR LH - BODY GROUND) 
    1. Disconnect the A6 cooling fan motor LH connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      A6-2 (E1) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR LH - BODY GROUND) 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR LH - ECM) 
    1. Disconnect the A36 ECM connector.
    2. Disconnect the A6 cooling fan motor LH connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open) 

      Tester Connection Condition Specified Condition
      A6-3 (SI) - A36-32 (RFC) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A6-3 (SI) or A36-32 (RFC) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE COOLING FAN MOTOR LH. Refer to  REMOVAL [10/2018 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR LH - ECM) 

  6. CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR RH POWER SOURCE CIRCUIT) 
    1. Disconnect the c1 cooling fan motor RH connector.
    2. Measure the voltage according to the value(s) in the table below.
      GTY810603Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Cooling Fan Motor RH)

      Standard Voltage

      Tester Connection Condition Specified Condition
      c1-1 (+B) - c1-2 (GND) Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR RH POWER SOURCE CIRCUIT) 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR RH - EFI-MAIN NO. 1 RELAY) 
    1. Disconnect the c1 cooling fan motor RH connector.
    2. Remove the EFI-MAIN NO. 1 relay from the No. 1 engine room relay block.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open) 

      Tester Connection Condition Specified Condition
      c1-4 (IG) - 3 (EFI-MAIN NO. 1 relay) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      c1-4 (IG) or 3 (EFI-MAIN NO. 1 relay) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR RH - EFI-MAIN NO. 1 RELAY) 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR RH - BODY GROUND) 
    1. Disconnect the c1 cooling fan motor RH connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open) 

      Tester Connection Condition Specified Condition
      c1-2 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR RH - BODY GROUND) 

    Result: 

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR RH - ECM) 
    1. Disconnect the A36 ECM connector.
    2. Disconnect the c1 cooling fan motor RH connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open) 

      Tester Connection Condition Specified Condition
      c1-3 (SI) - A36-32 (RFC) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      c1-3 (SI) or A36-32 (RFC) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE COOLING FAN MOTOR RH. Refer to  REMOVAL [10/2018 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR RH - ECM) 

  10. CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR LH - ECM) 
    1. Disconnect the A36 ECM connector.
    2. Disconnect the A6 cooling fan motor LH connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A36-32 (RFC) - A6-3(SI) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE COOLING FAN MOTOR LH. Refer to  REMOVAL [10/2018 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR LH - ECM) 

  11. CHECK HARNESS AND CONNECTOR (COOLING FAN MOTOR RH - ECM) 
    1. Disconnect the A36 ECM connector.
    2. Disconnect the c1 cooling fan motor RH connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A36-32 (RFC) - c1-3 (SI) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE COOLING FAN MOTOR RH. Refer to  REMOVAL [10/2018 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN MOTOR RH - ECM) 

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