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GF54.21-P-4121-02T Battery Control Unit, Task



GF54.21-P-4121-02T Battery Control Unit, Task

Task
The battery control unit (N82) measures the current and voltage of the battery (G1) as well as the temperature of the bus bar. The temperature of the bus bar is used to determine the temperature of the battery (G1). The voltage of the auxiliary battery (G1/7) is also measured. This data and the history of the battery are used to determine the working capacity of the battery (G1).

Together with the data of the overall vehicle, which is received by the interior CAN, the following measures are implemented for stabilization of the on-board electrical system:
^ Consumer group 1 switched off
^ Consumer group 2 switched off
^ Accessory socket switched off
^ Idle speed increase
^ Auxiliary battery (G1/7) cuts in for limp-home mode
^ Instability of vehicle power supply is displayed

The display in the instrument cluster (A1) informs the driver if a consumer group is switched off or if the vehicle power supply is unstable.