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Inspection Procedure

NOTE: When the seat belt control ECU is replaced with a new one, INITIALIZATION must be performed. (See INITIALIZATION  )
  1. CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT) 
    1. Disconnect the negative (-) terminal cable from the battery.
    2. Disconnect the O38 seat belt control ECU connector.
    3. Connect the negative (-) terminal cable to the battery.
    4. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      POWER SOURCE CIRCUIT

      Tester Connection Condition Specified Condition
      O38-3 (IG1) - Body ground Engine switch off Below 1 V
      Engine switch on (IG) 10 to 14 V
      O38-9 (+B) - Body ground Always 10 to 14 V
      Fig 1: Identifying O38 Seat Belt Control ECU Connector
      G05319656Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next step 

  2. CHECK HARNESS AND CONNECTOR (GROUND CIRCUIT) 
    1. Disconnect the negative (-) terminal cable from the battery.
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      GROUND CIRCUIT

      Tester Connection Condition Specified Condition
      O38-18 (PGND) - Body ground Always Below 1 Ω
      Fig 2: Identifying Harness And Connector (Ground Circuit)
      G05319657Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE SEAT BELT CONTROL ECU 

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