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Home >> Subaru >> 2017 >> BRZ Limited, Automatic Trans >> Repair and Diagnosis >> Electrical >> Charging Systems >> Charging system (FA20) >> Data monitor/active test
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Data monitor/active test

  1. Data monitor
    1. Use the SSM4 and follow the display to bring up the [Normal sampling] screen in order to inspect the computer data.
      CAUTION: Due to slight measurement differences and factors such as differences in the measurement environment or vehicle aged-related variation, the value of the data monitor/active test can be widely varied. It is difficult to obtain a precise standard value (determined value) for this. Therefore, there may be cases where a fault is present, even if it is within the reference value.
    PARTS DESCRIPTION

    Item name Description/display range Normal value Remarks
    (Main inspection items during a malfunction)
    [Control module voltage]
    • Indicates the battery voltage.
    • Display range: 0 to 65.535 V
    11 to 14 V: During idling Reference value:
    • IG ON: 12.5 V
    • While cranking: 9.834 V
    • At idling speed (after being warmed up): 13.359 V

    If the battery voltage 11 V or less, other systems may be affected.
    [Battery Current]
    • Indicates the battery current.
    • Display range: -125 to 125 A
    Changes depending on the alternator generation amount: After warming up, when driving When a malfunction occurs, it may be due to a problem with the IB voltage system or sensor power supply.
    [Battery Temperature]
    • Indicates the battery ambient temperature which is calculated from the output from the battery temperature sensor (battery current sensor ASSY).
    • Display range: -40 to 6513.5°C
    Changes depending on the actual temperature: After warming up, when driving When a malfunction occurs, it may be due to a problem with the THB voltage system or sensor power supply.
    [Alt Voltage - Non Active Test]
    • Indicates the requested voltage when forced driving of the regulator is not being carried out.
    • Display range: 0 - 80 V
    Changes depending on the battery fluid temperature, driving conditions (12.4 - 14.8 V): After engine is started When a malfunction occurs, it may be due to a problem with the charging control system.
    [Alt Voltage - Active Test]
    • Indicates the requested voltage when forced driving of the regulator is being carried out.
    • Display range: 0 - 80 V
    Value of the request instruction voltage when the active test [Alternator control] is carried out: After engine is started
    • Indicates the generation voltage during [Active Test].
    • When a malfunction occurs, it may be due to a problem with the charging control system.
    [ALT Duty]
    • Indicates the charging control signal.
    • Display range: 0 to 255%
    Changes depending on the alternator generation amount: During charging control When a malfunction occurs, it may be due to a problem with the charging control system.
    [Alternator control mode]
    • Indicates the alternator generation control mode.
    • Display range: 0 - 255%
    Changes depending on the alternator generation amount: During charging control When a malfunction occurs, it may be due to a problem with the charging control system.
    [Alternator Mechanical Error Status] Displayed when it is determined that there is a mechanical error on the alternator. 0 -
    [Alternator Electrical Output Error Status] Displayed when it is determined that there is an electrical error on the alternator. 0 -
    [Alternator High Temperature Error Status] Displayed when it is determined that there is a high temperature error on the alternator. 0 -
    [Alternator Communication Error Status] Displayed when it is determined that there is a communication error on the alternator. 0 -
    [Regulator Temperature] Alternator regulator temperature 170°C or less -
  2. Active test
    1. Using SSM4, display the [Active Test] screen according to the screen and perform the system operation check.
    PARTS DESCRIPTION

    Item Contents Restrictions
    [Alternator control] Increases or decreases the alternator generation request voltage.
    Able to request within the range of 12.8 - 14.3 V.
    While engine running