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Main Body ECU Communication Stop Mode [11/2021 - ]: Procedure

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  1. CHECK FOR OPEN IN CAN BUS LINES (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) MAIN LINE) 
    1. Disconnect the cable from the negative (-) battery terminal.
    2. Disconnect the D50 main body ECU (multiplex network body ECU) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      D50-2 (CANH) - D50-1 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω

      Result

      Result 
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)) 

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (BECU SIGNAL CIRCUIT) 
    1. Remove the main body ECU (multiplex network body ECU).

      Refer to REMOVAL [11/2021 - ]

    2. Reconnect the cable to the negative (-) battery terminal.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      MB-26 (BECU) - Body ground Always 11 to 14 V
      GTY1060297Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Power Distribution Box Assembly
      NOTE:

      Perform this inspection with the wire harness connected to the power distribution box assembly.

      Result

      Result 
      OK
      NG

    Result: 

    OK 

    CHECK ECU POWER SOURCE CIRCUIT. Refer to  IG Signal Circuit [11/2021 - ] 

    Result: 

    NG 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (BECU SIGNAL CIRCUIT) 
    1. Disconnect the cable from the negative (-) battery terminal.
    2. Disconnect the 9K power distribution box assembly connector.
    3. Reconnect the cable to the negative (-) battery terminal.
    4. Measure the voltage according to the value(s) in the table below.
      GTY1065065Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Power Distribution Box Assembly)

      Standard Voltage

      Tester Connection Condition Specified Condition
      9K-1 - Body ground Always 11 to 14 V

      Result

      Result 
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BECU SIGNAL CIRCUIT) 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (BECU SIGNAL CIRCUIT) 
    1. Disconnect the cable from the negative (-) battery terminal.
    2. Disconnect the 9C power distribution box assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      9C-11 - 9C-34 Cable disconnected from negative (-) battery terminal Below 1 Ω
      GTY1063248Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Power Distribution Box Assembly)

      Result

      Result 
      OK
      NG

    Result: 

    OK 

    REPLACE POWER DISTRIBUTION BOX ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BECU SIGNAL CIRCUIT) 

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