DSD Information System
Home >> Toyota >> 2021 >> Highlander LE, 4WD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Communication Devices >> Can Communication System (Except HV) - Circuit Tests (1 Of 8) & Diagnostic Codes >> CAN COMMUNICATION SYSTEM (for Gasoline Model) >> Main Body ECU Communication Stop Mode [11/2023 - ] >> Procedure

Main Body ECU Communication Stop Mode [11/2023 - ]: Procedure

  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 H135 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
      H135-2 (CANH) - H135-1 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      GTY1178276Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Main Body ECU (Multiplex Network Body ECU))

      Result

      Proceed to 
      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 [11/2023 - ]

    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
      GTY1178160Courtesy 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

      Proceed to 
      OK
      NG

    Result: 

    OK 

    CHECK ECU POWER SOURCE CIRCUIT 

    Refer to IG Signal Circuit [11/2023 - ]

    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 8E 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.
      GTY1178477Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Power Distribution Box Assembly)

      Standard Voltage

      Tester Connection Condition Specified Condition
      8E-23 - Body ground Always 11 to 14 V

      Result

      Proceed to 
      OK
      NG

    Result: 

    OK 

    REPLACE POWER DISTRIBUTION BOX ASSEMBLY 

    Refer to REMOVAL [11/2023 - ]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BECU SIGNAL CIRCUIT) 

Diesel-Data.com