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Inspection Procedure

NOTE: When using the Techstream with the engine switch off to troubleshoot:
Connect the Techstream to the vehicle, and turn a courtesy switch on and off at 1.5 second intervals until communication between the Techstream and vehicle begins.
  1. CHECK HARNESS AND CONNECTOR (REAR JUNCTION BLOCK ECU - MAP LIGHT) 
    Fig 1: Identifying Terminals Of S62 Junction Block And X6 Light Connectors
    G06198354Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the S62 junction block connector.
    2. Disconnect the X6 light connector.
    3. Measure the resistance and voltage according to the value(s) in the table below.

      Standard resistance 

      SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      S62-9 (LIN) - X6-2 (LIN) Always Below 1 Ω
      S62-9 (LIN) or X6-2 (LIN) - Body ground Always 10 kΩ or higher

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      S62-9 (LIN) or X6-2 (LIN) - Body ground Always Below 1 V

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      OK: Go to next step 

  2. CHECK MAP LIGHT (BATTERY VOLTAGE AND GROUND) 
    1. Disconnect the X4 light connector.
    2. Measure the resistance and voltage according to the value(s) in the table below.

      Standard resistance 

      SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      X4-16 (GND9) - Body ground Always Below 1 Ω

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      X4-6 (+B) - Body ground Always 11 to 14 V
      Fig 2: Identifying X4 Map Light Connector Terminal
      G06198355Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      OK: Go to next step 

  3. REPLACE MAP LIGHT ASSEMBLY (OVERHEAD JUNCTION BLOCK) 
    1. Temporarily replace the map light with a new or normally functioning one (see REMOVAL ).
    2. Clear the DTC (see DTC CHECK/CLEAR  ).
  4. CHECK FOR DTC 
    1. Recheck for DTC (see DTC CHECK/CLEAR  ).

      OK: 

      DTC B2405 is not output. 

      NG: REPLACE LUGGAGE ROOM JUNCTION BLOCK (REAR JUNCTION BLOCK ECU) 

      OK: END (MAP LIGHT IS DEFECTIVE)