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Inspection Procedure

WARNING: This page is about a different car, the 2007 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT FUSE 
    1. Inspect the ECU-IG No.2 fuse in the instrument panel junction block assembly.

      Resistance: 

      Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to Next step 

  2. INSPECT IG1 RELAY 
    1. Inspect IG1 relay continuity.
      1. Remove the IG1 relay from the instrument panel J/B assembly.
      2. Measure the resistance according to the value(s) in the table below.
        Fig 1: Inspecting Relay
        G04966287Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Resistance 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester connection Condition Specified resistance
        3 - 5 Always 10 kΩ or higher
        3 - 5 Apply B+ between the terminal 1 and 2 Below 1 Ω

    NG: REPLACE RELAY 

    OK: Go to Next step 

  3. INSPECT HEADLIGHT BEAM LEVEL CONTROL ECU 
    1. Disconnect the H17 connector of headlight beam level control ECU.
    2. Measure the voltage according to the value(s) in the table below.
      Fig 2: Disconnecting H17 Headlight Beam Level Control ECU Connector Terminals
      G05273868Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      H17-14 (IG) - H17-1 (GND) Ignition switch OFF → ON Below 1 V → 10 to 14 V

    NG: Go to step 4 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

  4. CHECK HARNESS AND CONNECTOR (HEADLIGHT BEAM LEVEL CONTROL ECU BODY GROUND) 
    1. Disconnect the H17 connector of headlight beam level control ECU.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 3: Disconnecting H17 Connector Of Headlight Beam Level Control ECU Connector Terminals
      G05273869Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      H17-1 (GND) - Body ground Always Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next step 

  5. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (POWER SOURCE CIRCUIT) 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 4: Identifying 1A Instrument Panel Junction Block Assembly Front Side Connector Terminals
      G05273777Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      1A-1 - Body ground Always 10 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - INSTRUMENT PANEL J/B ASSEMBLY) 

    OK: Go to Next step 

  6. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 5: Identifying 1F Instrument Panel Junction Block Assembly Front Side Connector Terminals
      G05273779Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      1F-19 - Body ground Ignition switch OFF → ON Below 1 V → 10 to 14 V

    NG: Go to step 7 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (INSTRUMENT PANEL J/B ASSEMBLY - LEVEL CONTROL ECU) 

  7. INSPECT IGNITION SWITCH 
    1. Disconnect the ignition switch connector.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 6: Identifying I14 Ignition Switch Connector Terminals
      G05273780Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified resistance
      2 - 4 Ignition switch OFF 10 kΩ or higher
      2 - 4 Ignition switch ON Below 1 Ω

    NG: REPLACE IGNITION SWITCH 

    OK: Go to Next step 

  8. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 7: Identifying 1I Instrument Panel Junction Block Assembly Front Side Connector Terminals
      G05273776Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      1I-4 - Body ground Always 10 to 14 V

    NG: REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

    OK: Go to Next step 

  9. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 8: Identifying 1I Instrument Panel Junction Block Assembly Front Side Connector Terminals
      G05273776Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      1I-9 - Body ground Ignition switch OFF → ON Below 1 V → 10 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next step 

  10. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL J/B ASSEMBLY - BODY GROUND) 
    1. Disconnect the 1F connector from the instrument panel junction block assembly.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 9: Identifying 1F Instrument Panel Junction Block Assembly Front Side Connector Terminals
      G05273779Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      1F-10 - Body ground Always Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

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