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Inspection Procedure

WARNING: This page is about a different car, the 2008 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 and AM1 fuse in the instrument panel junction block assembly.

      Resistance: 

      Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to Next step 

  2. INSPECT RELAY 
    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 AFS ECU 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 2: Identifying A14 AFS ECU Connector Terminals
      G05273886Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      A14-2 (IG) - A14-1 (E1) Ignition switch OFF → ON Below 1 V → 10 to 14 V
      A14-12 (IGS) - A14-1 (E1) 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 (AFS ECU - BODY GROUND) 
    1. Disconnect the A14 connector from headlight swivel ECU assembly.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 3: Identifying A14 Headlight Swivel ECU Assembly Connector Terminals
      G05273887Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      A14-1 (E1) - Body ground Always Below 1 Ω
      A14-11 (E1S) - Body ground Always Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next step 

  5. INSPECT INSTRUMENT PANEL J/B ASSEMBLY 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 4: 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  6

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

  6. INSPECT INSTRUMENT PANEL J/B ASSEMBLY (POWER SOURCE CIRCUIT) 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 5: 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 

  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 condition
      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 J/B ASSEMBLY 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 7: Identifying 1I Instrument Panel Junction Block Assembly Back 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 J/B ASSEMBLY 

    OK: Go to Next step 

  9. INSPECT INSTRUMENT PANEL J/B ASSEMBLY 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 8: Identifying 1I Instrument Panel Junction Block Assembly Back 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 J/B ASSEMBLY 

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