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Inspection Procedure

  1. CHECK WHETHER DTC OUTPUT RECURS (DTC B2321) 
    1. Connect Techstream to the DLC3.
    2. Turn the ignition switch ON and turn the tester on.
    3. Clear the DTCs.
    4. Recheck the DTCs.

      Result 

      DTC OUTPUT REFERENCE

      Display (DTC Output) Proceed to
      B2321 A
      No DTC output B

    B: SYSTEM IS OK 

    A: Go to Next Step 

  2. READ VALUE OF TECHSTREAM (COMMUNICATION D DOOR MOTOR) 
    1. Connect Techstream to the DLC3.
    2. Turn the ignition switch ON and turn the tester on.
    3. Read the indication displayed on the tester.

      Main body 

      MAIN BODY REFERENCE

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Communication D-Door Motor Connection status between power window regulator motor assembly (driver door) and main body ECU / OK or Stop OK: Connection Stop:
      No connection
      -

      OK: 

      OK is displayed on Techstream screen. 

    OK: REPLACE INSTRUMENT PANEL JUNCTION BLOCK (MAIN BODY ECU) 

    NG: Go to Next Step 

  3. CHECK WIRE HARNESS (MAIN BODY ECU - REGULATOR MOTOR) 
    1. Disconnect the H4 motor connector.
    2. Disconnect the E15 junction block connector.
      Fig 1: Identifying H4 Motor Connector And E15 Junction Block Connector Terminal
      G05586450Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      H4-9 (LIN) -E15-23 (LIN2) Below 1 Ω
      H4-9 (LIN) or E15-23 (LIN2) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to Next Step 

  4. CHECK WHETHER DTC OUTPUT RECURS(DTC B2321) 
    1. Connect Techstream to the DLC3.
    2. Turn the ignition switch ON and turn the tester on.
    3. Clear the DTCs.
    4. Check whether DTC B2321 recurs 10 seconds or more after the ignition switch is turned ON.

      OK: 

      No DTC is output. 

    NG: REPLACE POWER WINDOW REGULATOR MOTOR ASSEMBLY (for Driver Side) 

    OK: REPLACE INSTRUMENT PANEL JUNCTION BLOCK (MAIN BODY ECU)