Automatic 12V Battery Charge Control

SYSTEM

AUTOMATIC 12V BATTERY CHARGE CONTROL : System Description


SYSTEM DIAGRAM







DESCRIPTION

The automatic 12V battery charge control is a control to reduce the frequency of battery discharge by automatically charging the 12V battery in case the 12V battery voltage is low when the key switch is turned to ON
or the vehicle is left unattended for a long time.
When VCM judges a need for automatic charge, VCM controls the DC/DC converter and the system main relay and charges the 12V battery using the Li-ion battery power.
For 12V battery charge control during READY condition, refer to "POWER VOLTAGE VARIABLE
CONTROL SYSTEM : System Description".





NOTE:
When any of the following operations is performed, the 12V battery automatic charge control is canceled: 1)
Vehicle to the READY state, 2) Normal charge, 3) Quick charge, 4) Timer/remote A/C ON.

CONTROL DESCRIPTION

Power ON
VCM monitors the 12V battery voltage during POWER ON cycle and immediately starts charging when VCM
judges that the voltage is lowered.
NOTE:
VCM does not perform the automatic 12V battery charge control when the shift position is in a range other than "P" range.
When Vehicle is Not Used for A Long Time
VCM measures the time of no operation using its internal timer. If the time of no operation reaches 120 hours, VCM performs automatic charge for 5 minutes.
VCM resets the no operation status continuous time when the vehicle satisfies one of the following conditions.
- READY continues for more than 5 minutes.
- Normal charge continues for more than 5 minutes.
- Quick charge continues for more than 5 minutes.
- Timer air conditioning or remote air conditioning continues for more than 5 minutes.
NOTE:
- During automatic 12V battery charge, the charging status indicator blinks.
- The automatic 12V battery charge control does not start within approximately one hour when the power switch is turned ON/OFF.