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System Main Relay: Inspection

  1. INSPECT NO. 1 SYSTEM MAIN RELAY 
    NOTE: Connectors B and C have the same shape. Identify each connector by the wire harness length (L) and the wire harness color on the terminal 2 side.
    WIRE HARNESS LENGTH AND COLOR SPECIFICATION

    Connector Wire Harness Length (L) Wire Harness Color
    B Short Yellow
    C Long Black
    Fig 1: Inspecting No 1 System Main Relay
    G04473970Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the resistance.
      1. Measure the resistance between the connectors.

        Standard resistance 

        TERMINALS RESISTANCE SPECIFICATION

        Tester Connection Specified Condition
        Positive terminal - Negative terminal 10 kΩ or higher
        A-2 (CONT2) - B-2 (CONT2) Below 1 Ω
        A-3 (CONT3) - C-2 (CONT3) Below 1 Ω
        B-1 (GND) - GND Below 1 Ω
        C-1 (GND) - GND Below 1 Ω

        If the results are not as specified, replace the No. 1 system main relay.

      2. Apply battery voltage between the GND terminal and CONT1 terminal of the connector A, then measure the resistance between the positive and negative terminals.

        Standard resistance: 

        Below 1 Ω 

        If the results are not as specified, replace the No. 1 system main relay.

    2. Inspect the resistance.
      1. Measure the resistance between the GND terminal and CONT1 terminal of the connector A.

        Standard resistance: 

        70 to 160 kΩ 

        If the results are not as specified, replace the No. 1 system main relay.

  2. INSPECT NO. 2 SYSTEM MAIN RELAY 
    1. Install the 2 installed nuts to the negative and positive terminals.

      Torque: 5.6 N*m (57 kgf*cm, 50 in.*lbf) 

    2. Check the resistance.
      1. Measure the resistance between the positive and negative terminals.

        Standard resistance: 

        10 kΩ or higher 

        If the result is not as specified, replace the No. 2 system main relay.

      2. Apply battery voltage between the connector terminals, then measure the resistance between the positive and negative terminals.

        Standard resistance: 

        Below 1 Ω 

        If the result is not as specified, replace the No. 2 system main relay.

        Fig 2: Inspecting No 2 System Main Relay
        G04473971Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Inspect the resistance.
      1. Measure the resistance between the connector terminals.

        Standard resistance: 

        20 to 50 kΩ 

        If the result is not as specified, replace the No. 2 system main relay.

  3. INSPECT NO. 3 SYSTEM MAIN RELAY 
    1. Install the 2 installed nuts to the negative and positive terminals.

      Torque: 5.6 N*m (57 kgf*cm, 50 in.*lbf) 

    2. Check the resistance.
      1. Measure the resistance between the positive and negative terminals.

        Standard resistance: 

        10 kΩ or higher 

        If the result is not as specified, replace the No. 3 system main relay.

        Fig 3: Inspecting No 3 System Main Relay
        G04473972Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Apply battery voltage between the connector terminals, then measure the resistance between the positive and negative terminals.

        Standard resistance: 

        Below 1 Ω 

        If the result is not as specified, replace the No. 3 system main relay.

    3. Inspect the resistance.
      1. Measure the resistance between the connector terminals.

        Standard resistance: 

        20 to 50 kΩ 

        If the result is not as specified, replace the No. 3 system main relay.

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