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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 Q38 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 

    VOLTAGE SPECIFICATION

    Tester Connection Condition Specified Condition
    Q38-3 (IG1) - Body ground Engine switch off Below 1 V
    Engine switch on (IG) 10 to 14 V
    Q38-9 (+B) - Body ground Always 10 to 14 V
    Fig 1: Checking Harness And Connector (Power Source Circuit)
    G05827378Courtesy 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 

    RESISTANCE SPECIFICATION

    Tester Connection Condition Specified Condition
    Q38-18 (PGND) -Body ground Always Below 1 Ω
    Fig 2: Checking Harness And Connector (Ground Circuit)
    G05827379Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE SEAT BELT CONTROL ECU 

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