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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. READ VALUE OF INTELLIGENT TESTER 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the ignition switch to the ON position and press the intelligent tester main switch ON.
    3. Select the items below in the DATA LIST, and read the displays on the intelligent tester.

      BODY: 

      ITEM MEASUREMENT CONDITION CHART

      Item Measurement Item/ Display (Range) Normal Condition Diagnostic Note
      ACC SW ACC SW signal/ON or OFF ON: Ignition key is in ACC, ON or START position
      OFF: Ignition key is in OFF position      		 -
      IG SW IG SW signal/ON or OFF ON: Ignition key is in ON or START position
      OFF: Ignition key is in OFF or ACC position      		 -

    NG: Go to step 2 

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

  2. INSPECT FUSE 
    1. Inspect the ECU-ACC fuse, ECU-IG No.1 fuse and AM1 fuse in the instrument panel junction block assembly.

      Resistance: 

      Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to Next step 

  3. INSPECT RELAY 
    1. Inspect ACC relay continuity.
      1. Remove the ACC relay from the instrument panel J/B.
      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
    2. Inspect IG1 relay continuity.
      1. Remove the IG1 relay from the instrument panel J/B.
      2. Measure the resistance according to the value(s) in the table below.
        Fig 2: Inspecting IG1 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 

  4. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (ACC, IG) 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 3: Identifying 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-3 - Body ground Ignition switch is OFF → ACC, ON Below 1 V → 10 to 14 V
      1I-9 - Body ground Ignition switch is OFF → ON Below 1 V → 10 to 14 V

    NG: Go to step 5 

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

  5. INSPECT JUNCTION BLOCK NO.2 (POWER SOURCE CIRCUIT) 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 4: Identifying Instrument Panel Junction Block Assembly Front Side Connector Terminals
      G05273777Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION

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

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) 

    OK: Go to Next step 

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

  7. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK 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 6: Identifying 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: Go to Next step 

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

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      2 - 3 Ignition switch OFF 10 kΩ or higher
      2 - 4 Ignition switch OFF 10 kΩ or higher
      2 - 3 Ignition switch ACC Below 1 Ω
      2 - 4 Ignition switch ON Below 1 Ω

    NG: REPLACE IGNITION SWITCH 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - IGNITION SWITCH) 

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