Note:
Battery charge status is determined by the system APM (Advanced Power Management). both when driving and when the car is stationary.
During driving:
Balancing of the battery's charge and discharge current.
Calculation of the current's path at engine start to determine battery status.
Data information is transmitted by the intelligent battery sensor (IBS) via the bit-serial interface (BSD) to the engine control unit.
When the vehicle is stationary the resting current is measured cyclically to identify energy loss. The measuring values are stored in the memory of the intelligent battery sensor and are transmitted to the engine control unit at the next engine start.
The engine control unit stores the following values for the battery charge status' history:
Battery charge status for the last five days.
Histogram of the charge status with time areas 0-20%, 20-40%, 40-60%, 60-80%, and 80-100%. The charge status histogram is reset at registration of battery change or that the engine control unit is programmed.
Test conditions:
Ignition on, engine off.
No faults in the system.
Procedure:
Start the function.
The following data is read out from the intelligent battery sensor.
Currently registered battery capacity.
Odometer reading at last battery change.
Current odometer reading.
For more information, press the button "YES" to show the following data.
Charge status for the last five days.
Histogram for charge status.