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Interior Light Circuit: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. PERFORM ACTIVE TEST USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Main Body / Active Test.
    5. Check that the lights operate.
      MAIN BODY

      Tester Display Test Part Control Range Diagnostic Note
      Illuminated Entry System Personal light and No. 1 room light assembly ON/OFF Interior light door switch DOOR and all doors closed

      OK

      Each light fades in.

    NG → See step   2 

    OK → See step   7 

  2. CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - MAP LIGHT ASSEMBLY) 
    1. Disconnect the U3 map light assembly connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      U3-20 (+B1) - Body ground Power switch off 11 to 14 V

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. INSPECT MAP LIGHT ASSEMBLY 
    1. Remove the map light assembly. Refer to REMOVAL .
    2. Inspect the map light assembly. Refer to INSPECTION .

      OK

      Map light assembly is normal.

    NG → See step   9 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (MAP LIGHT ASSEMBLY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) 
    1. Disconnect the 2A instrument panel junction block assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U3-11 (CTY) - 2A-52 Always Below 1 Ω
      U3-11 (CTY) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  5. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 
    1. Remove the instrument panel junction block assembly. Refer to REMOVAL .
    2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly. Refer to REMOVAL .
      Fig 1: Inspecting 2A & MB Connector Terminals
      GTY335666Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2A-52 - MB-1 (ILE) Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (Instrument Panel Junction Block Assembly)

    NG → See step   8 

    OK → See step   6 

  6. REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL 
  7. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE  
  8. REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL 
  9. REPLACE MAP LIGHT ASSEMBLY. Refer to  REMOVAL 
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