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Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.
  1. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE COOLING FAN) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Enter the following menus: Powertrain / Engine / Active Test / Control the Cooling Fan
    4. Check the operation of the cooling fan while operating it using the Techstream

    OK 

    FAN OPERATION CHART

    Tester Operation Fan Operation
    ON Cooling fan rotates
    OFF Cooling fan stopped

    Result 

    RESULT CHART

    Result Proceed to
    OK A
    NG (Main fan) B
    NG (Sub fan) C
    NG (Main and sub fans) D

    B: Go to step   2 

    C: Go to step   13 

    D: Go to step   24 

    A: REPLACE ECM  (See ECM )

  2. INSPECT COOLING FAN SYSTEM (FOR MAIN FAN) 
    1. Disconnect the ECM connector
    2. Turn the engine switch on (IG)
    3. Check the operation of the cooling fan

    OK: The cooling fan rotates. 

    NG: Go to step   4 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (ECM - COOLING FAN ECU (FOR MAIN FAN)) 
    1. Disconnect the cooling fan ECU connector
    2. Disconnect the ECM connector
    3. Measure the resistance according to the value(s) in the table below

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    A5-19 (RFC) - B14-2 (SI) Always Below 1 Ω
    Fig 1: Identifying Terminals Of Cooling Fan ECU Connector
    G05750281Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE COOLING FAN ECU (FOR MAIN FAN) 

  4. CHECK HARNESS AND CONNECTOR (ECM - COOLING FAN ECU (FOR MAIN FAN)) 
    1. Disconnect the cooling fan ECU connector
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    A5-19 (RFC) or B14-2 (SI) - Body ground Always 10 kΩ or higher
    Fig 2: Identifying Terminals Of Cooling Fan ECU Connector
    G05750281Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  5. INSPECT COOLING FAN MOTOR (FOR MAIN FAN) 
    1. Inspect the cooling fan motor (See COOLING FAN MOTOR )

    NG: REPLACE COOLING FAN MOTOR (FOR MAIN FAN)  (See COOLING FAN MOTOR )

    OK: Go to next step 

  6. CHECK ECU POWER SOURCE CIRCUIT (FOR MAIN FAN) 
    1. Disconnect the cooling fan ECU connector.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Switch Condition Specified Condition
    B14-1 (+B1) - B14-3 (E1) Engine switch on (IG) 11 to 14 V
    Fig 3: Identifying Terminals Of Cooling Fan ECU Connector
    G05750283Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step   7 

    OK: REPLACE COOLING FAN ECU (FOR MAIN FAN) 

  7. CHECK HARNESS AND CONNECTOR (COOLING FAN ECU (FOR MAIN FAN) - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    B14-3 (E1) - Body ground Always Below 1 Ω
    Fig 4: Identifying Terminals Of Cooling Fan ECU Connector
    G05750284Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  8. INSPECT FAN NO. 1 RELAY 
    1. Remove the FAN No. 1 relay from the engine room No. 1 relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    3-5 Normal 10 kΩ or higher
    3-5 Battery voltage applied between terminals 1 and 2 Below 1 Ω
    Fig 5: Inspecting Fan No. 1 Relay
    G05750285Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FAN NO. 1 RELAY 

    OK: Go to next step 

  9. CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY - BATTERY) 
    1. Remove the FAN No. 1 relay from the engine room No. 1 relay block.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    3 (FAN No.1 relay) - Body ground Always 11 to 14 V
    Fig 6: Identifying Terminals Of Fan No. 1 Relay
    G05750286Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step   12 

    OK: Go to next step 

  10. CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY - LH-IG FUSE) 
    1. Remove the FAN No. 1 relay from the engine room No. 1 relay block
    2. Measure the voltage according to the value(s) in the table below

      Standard Voltage 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    1 (FAN No 1 relay) - Body ground Always 11 to 14 V
    Fig 7: Identifying Terminals Of Fan No. 1 Relay
    G05750286Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  11. CHECK HARNESS AND CONNECTOR (FAN NO. 1 RELAY - BODY GROUND) 
    1. Remove the FAN No. 1 relay from the engine room No. 1 relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    2 (FAN No.1 relay) - Body ground Always Below 1 Ω
    Fig 8: Identifying Terminals Of Fan No. 1 Relay
    G05750286Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 1 RELAY - BODY GROUND) 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN ECU (FOR MAIN FAN) - FAN NO. 1 RELAY) 

  12. INSPECT FUSIBLE LINK BLOCK (FAN NO. 1 FUSE) 
    1. Remove the fusible link block from the engine room No 1 relay block.
    2. Measure the resistance according to the value(s) in the table below.
    Fig 9: Identifying Fusible Link Block Terminals
    G05750289Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    1F-1 - 1F-2 Always Below 1 Ω

    NG: REPLACE FUSIBLE LINK BLOCK 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 1 RELAY - BATTERY) 

  13. INSPECT COOLING FAN SYSTEM (FOR SUB FAN) 
    1. Disconnect the ECM connector.
    2. Turn the engine switch on (IG).
    3. Check the operation of the cooling fan.

    OK: The cooling fan rotates. 

    NG: Go to step   15 

    OK: Go to next step 

  14. CHECK HARNESS AND CONNECTOR (COOLING FAN ECU (FOR SUB FAN) - ECM) 
    1. Disconnect the cooling fan ECU connector
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    A5-19 (RFC) - B15-2 (SI2) Always Below 1 Ω
    Fig 10: Identifying Terminals Of Cooling Fan ECU Connector
    G05750290Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE COOLING FAN ECU (FOR SUB FAN) 

  15. CHECK HARNESS AND CONNECTOR (COOLING FAN ECU (FOR SUB FAN) - ECM) 
    1. Disconnect the cooling fan ECU connector.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    A5-19 (RFC) or B15-2 (SI2) - Body ground Always 10 kΩ or higher
    Fig 11: Identifying Terminals Of Cooling Fan ECU Connector
    G05750290Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  16. INSPECT COOLING FAN MOTOR (FOR SUB FAN) 
    1. Inspect the cooling fan motor (See COOLING FAN MOTOR )

    NG: REPLACE COOLING FAN MOTOR (FOR SUB FAN)  (See COOLING FAN MOTOR )

    OK: Go to next step 

  17. CHECK ECU POWER SOURCE CIRCUIT (FOR SUB FAN) 
    1. Disconnect the cooling fan ECU connector
    2. Turn the engine switch on (IG)
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Switch Condition Specified Condition
    B15-1 (+B2) - B15-3 (E2) Engine switch on (IG) 11 to 14 V
    Fig 12: Identifying Terminals Of Cooling Fan ECU Connector
    G05750292Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step   18 

    OK: REPLACE COOLING FAN ECU (FOR SUB FAN) 

  18. CHECK HARNESS AND CONNECTOR (COOLING FAN ECU (FOR SUB FAN) - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    B15-3 (E2) - Body ground Always Below 1 Ω
    Fig 13: Identifying Terminals Of Cooling Fan ECU Connector
    G05750293Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  19. INSPECT FAN NO. 2 RELAY 
    1. Remove the FAN No. 2 relay from the engine room No. 1 relay block.
    2. Measure the resistance according to the value(s) in the table below.
    Fig 14: Inspecting Fan No. 2 Relay
    G05750285Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    3-5 Normal 10 kΩ or higher
    3-5 Battery voltage applied between terminals 1 and 2 Below 1 Ω

    NG: REPLACE FAN NO. 2 RELAY 

    OK: Go to next step 

  20. CHECK HARNESS AND CONNECTOR (FAN NO. 2 RELAY - BATTERY) 
    1. Remove the FAN No. 2 relay from the engine room No. 1 relay block.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    3 (FAN No. 2 relay) - Body ground Always 11 to 14 V
    Fig 15: Identifying Terminals Of Fan No. 2 Relay
    G05750295Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step   23 

    OK: Go to next step 

  21. CHECK HARNESS AND CONNECTOR (FAN NO. 2 RELAY - LH-IG FUSE) 
    1. Remove the FAN No. 2 relay from the engine room No. 1 relay block.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    1 (FAN No. 2 relay) - Body ground Always 11 to 14 V
    Fig 16: Identifying Terminals Of Fan No. 2 Relay
    G05750295Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  22. CHECK HARNESS AND CONNECTOR (FAN NO. 2 RELAY - BODY GROUND) 
    1. Remove the FAN No. 2 relay from the engine room No. 1 relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    2 (FAN No. 2 relay) - Body ground Always Below 1 Ω
    Fig 17: Identifying Terminals Of Fan No. 2 Relay
    G05750295Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 2 RELAY - BODY GROUND) 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (COOLING FAN ECU (FOR SUB FAN) - FAN NO. 2 RELAY) 

  23. INSPECT FUSIBLE LINK BLOCK (FAN NO. 2 FUSE) 
    1. Remove the fusible link block from the engine room No. 1 relay block.
    2. Measure the resistance according to the value(s) in the table below.
    Fig 18: Identifying Fusible Link Block Terminals
    G05750289Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    FAN No. 2 fuse Always Below 1 Ω

    NG: REPLACE FUSIBLE LINK BLOCK 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (FAN NO. 2 RELAY - BATTERY) 

  24. INSPECT COOLING FAN SYSTEM 
    1. Disconnect the ECM connector.
    2. Turn the engine switch on (IG).
    3. Check the operation of the cooling fan.

    OK: The cooling fan rotates. 

    NG: Go to step   26 

    OK: Go to next step 

  25. CHECK HARNESS AND CONNECTOR (ECM - COOLING FAN ECU (FOR MAIN AND SUB FAN)) 
    1. Disconnect the cooling fan ECU connector
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    A5-19 (RFC) - B14-2 (SI) Always Below 1 Ω
    A5-19 (RFC) - B15-2 (SI2) Always Below 1 Ω
    Fig 19: Identifying Terminals Of Cooling Fan ECU Connector
    G05750299Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE ECM  (See ECM )

  26. CHECK HARNESS AND CONNECTOR (ECM - COOLING FAN ECU (FOR MAIN AND SUB FAN)) 
    1. Disconnect the cooling fan ECU connector.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    A5-19 (RFC), B14-2 (SI) or B15-2 (SI2) - Body ground Always 10 kΩ or higher
    Fig 20: Identifying Terminals Of Cooling Fan ECU Connector
    G05750299Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  27. INSPECT FUSE (LH-IG FUSE) 
    1. Remove the LH-IG fuse from the cowl side junction block LH.
    2. Measure the resistance according to the value(s) in the table below

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    LH-IG fuse Always Below 1 Ω
    Fig 21: Identifying LH-IG Fuse
    G05750301Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FUSE (LH-IG FUSE) 

    OK: Go to next step 

  28. INSPECT MAIN BODY ECU LH (IG1 RELAY) 
    1. Disconnect the main body ECU LH (cowl side junction block LH) connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    LL-6 - LM-1 Normal 10 kΩ or higher
    LL-6 - LM-1 Battery voltage applied between terminals LD-8 and LD-13 Below 1 Ω
    Fig 22: Identifying Terminals Of Main Body ECU LH Connector
    G05750302Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH) 

    OK: Go to next step 

  29. CHECK HARNESS AND CONNECTOR (IG1 RELAY - FAN NO. 1 RELAY) 
    1. Disconnect the main body ECU LH (cowl side junction block LH) connector
      Fig 23: Identifying Terminals Of Fan No. 1 Relay
      G05750286Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Remove the FAN No. 1 relay from the engine room No 1 relay block.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    LL-6 - 1 (FAN No. 1 relay) Always Below 1 Ω
    Fig 24: Identifying Terminals Of Fan No. 1 Relay
    G05750304Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  30. CHECK HARNESS AND CONNECTOR (IG1 RELAY POWER SOURCE) 
    1. Disconnect the main body ECU (cowl side junction block LH) connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Switch Condition Specified Condition
    LM-1 - Body ground Engine switch on (IG) 11 to 14 V
    Fig 25: Identifying Terminals Of Main Body ECU Connector
    G05750305Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step   32 

    OK: Go to next step 

  31. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - BODY GROUND) 
    1. Disconnect the main body ECU LH (cowl side junction block LH) connector
    2. Measure the resistance according to the value(s) in the table below

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    LD-8 - Body ground Always Below 1 Ω
    Fig 26: Identifying Terminals Of Main Body ECU LH Connector
    G05750306Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (MAIN BODY ECU LH - BODY GROUND) 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - MAIN BODY ECU LH) 

  32. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - POWER SOURCE CONTROL ECU) 
    1. Disconnect the main body ECU LH (cowl side junction block LH) connector
    2. Disconnect the power source control ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    J55-34 (IG1D) - LD-13 (Main body ECU LH) Always Below 1 Ω
    Fig 27: Identifying Terminals Of Main Body ECU LH Connector
    G05750307Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START  (See HOW TO PROCEED WITH TROUBLESHOOTING )

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