5 Series E60 M5 (S85) SAL
-
the alternator is at full capacity
and
-
the battery charge state is too low.
Load peak reduction
If the charge state of the battery does not improve, even after the idling speed has been increased, the peak load in
the vehicle electrical system is reduced. The peak load reduction is achieved by the following actions:
-
Pulsing the load with pulse width modulation (PWM) signals
In this process, consumers (e.g. the electric auxiliary heater) are switched on and off for defined times.
To pulse the electric auxiliary heater, the power management outputs a PWM signal in the DME / DDE,
depending on the energy available. The PWM signal contains the information for the maximum switch-on power
available for the electric auxiliary heater. The frequency of the PWM signal is fixed at 160 Hertz (Hz).
-
Power draw reduced to a certain percentage.
-
Individual consumers are switched off in extreme situations when the power reduction achieved through pulsing
and reduced consumption is insufficient.
The load on the vehicle electrical system is reduced according to the table:
Priority of consumers
Power reduction
Control unit
Heated rear window
Pulsing
IHKA
Seat heating
level 2
SM
Seat heating
50 %
SM
Active seat
Off
SM
Heater blower
75 %
IHKA
Steering wheel heating
Pulsing
SZL
Heater blower
50 %
IHKA
Mirror heating
Off
TM
>from 09/2005: KGM
Heated rear window
Off
IHKA
Seat heating
Off
SM
Steering wheel heating
Off
SZL
Active seat ventilation
Off
SM
Heater blower
25 %
IHKA
Consumer shutoff
Consumers are switched off according to different criteria and are split into the following categories:
-
Convenience consumers
•
Heated rear window
•
Seat heating
•
Steering wheel heating
The convenience consumers are automatically switched off when the engine is switched off. The convenience
consumers can only be switched on again after the engine has been restarted.
SBT Power supply E60, E61, E63, E64
BMW AG - TIS
23.02.2013 20:12
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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