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Home >> Lexus >> 2009 >> LS 460L RWD >> Repair and Diagnosis >> Electrical >> Body Electrical >> Power Source/Wiring >> Electric Power Control System >> System Description
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System Description

  1. DESCRIPTION 
    1. The electric power control system is provided to supply power constantly to the vehicle equipped with many electronic systems.

      The electric power control ECU always monitors the battery condition. In accordance with the battery condition, the electric power control ECU implements various control measures on systems that operate while the vehicle is parked or systems that require a large amount of power in a short period of time.

  2. RECHARGE CONTROL 
    1. While the engine is running, the electric power control ECU monitors the battery recharging state.

      The ECU then adjusts the generated voltage so that the actual current value is close to the target current value.

      The ECU sends recharging control signals to the ECM via CAN communication.

  3. LOAD CONTROL 
    1. While the engine is running, the electric power control ECU temporarily limits the power consumption of large systems to optimize the battery recharging state.

      The ECU sends load control signals to load control related systems via CAN communication.

  4. POWER SAVE CONTROL WHILE PARKED 
    1. Depending on the amount of time the vehicle is parked, the electric power control ECU cuts power to systems that it determines to be unnecessary.

      The electric power control ECU uses the power cut relay to control power supplied to power cut linked parts.

  5. MESSAGE OF CHARGING SYSTEM 

    Details 

    DETAILS CHART

    Condition that leads to display Timing Display details Master caution operation Buzzer operation
    Generator malfunction When malfunction is detected
    • Check Generator
    • Have your vehicle checked by a dealer
    - Sound
    Load control operation When load control is performed Electrical equipment operation is limited - -
    Battery voltage drop When parked, electrical equipment usage leads to battery voltage drop
    • Low Battery
    • Start the engine
    Illuminate -
    Battery voltage detection malfunction When malfunction in battery voltage detection is detected
    • Check Power Control System
    • Have your vehicle checked by a dealer
    - -