Explanation Of Circuits
DC/DC Converter converts HV battery DC352 V to DC12 V, and supplies power to the vehicle lights, audio system and other units. And at the same time, charges the Battery (12V).
DC352 V is temporarily converted to alternating current in the transistor bridge circuit, and after voltage drop down in the transformer, converted to DC12 V after rectified and smoothed (direct current).
DC/DC Converter controls the output voltage so that the Battery (12V) terminal voltage becomes constant.
Motor generator control ECU sends the stop command to DC/DC Converter and receives the 12 V
charge system normal or abnormal status via NODD signal line.
This DTC is stored when the DC/DC Converter stops due to circuit failure or protection function and the Battery (12V) voltage becomes 11 V or less at READY ON.
DC/DC Converter malfunction information is sent from the DC/DC Converter to Motor generator control ECU via NODD signal line.
Moreover, this DTC may be detected when Cooling System malfunction (stop due to frozen piping, W/P malfunction, etc.) or high voltage insulation abnormality occurs.