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Shut Down of Auxiliary Consumers




Shut-Down of Auxiliary Consumers

Auxiliary consumer circuits are items such as the CD, DWA, LM, EGS and IHKA (rest function).

In order to ensure that the car is capable of starting, the charge level (SoC-State of Charge) of the battery is monitored when the vehicle is at rest.

The minimum battery SoC required to ensure that the car can be started again is a calculated value. The calculation takes into account the:

- Battery temperature measured over last few days
- Engine type
- Capacity of the battery fitted (11OAh for the 745i).

The SoC calculation is displayed as a percentage of battery capacity ( A fully charged battery is considered 80%).

If the charge level of the battery gets close to that calculated minimum level as a result of the operation of an auxiliary consumer unit, the Power Module instructs that circuit to switch off.

Two modes of operation are distinguished when shutting down auxiliary consumer circuits:

- Auxiliary consumer with terminal R on.
- Auxiliary consumer with terminal 0 (ignition off).