1 Series E81 130i (N52K) 3-door
E81, E87, E90, E91, E92, E93 from 03/2007 until 09/2007
[System overview ...]
E81, E82, E87, E90, E91, E92, E93 from 09/2007
[System overview ...]
Brief description of components
The following components are involved in the power supply:
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Alternator
The alternator generates the charge voltage for the battery and the power supply for the consumers. The
alternator generates a variable voltage, depending on the engine speed (alternator voltage).
The power management system regulates this variable voltage.
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Battery
The vehicle battery is fitted inside a plastic casing in the luggage compartment. The capacity of the battery
installed depends on the engine used and the equipment installed in the vehicle.
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Junction box
The junction box is fitted behind the glove box underneath the instrument panel.
The junction box consists of a power distributor and a control unit, the junction box electronics (JBE, see below).
The power distributor holds fuses and relays. The following relays are of particular importance for the power
supply:
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Terminal 15 relay
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Terminal 30g relay for consumer cutoff (see below under "System functions")
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Terminal 30g-f relay for cutoff in case of fault (see below under "System functions")
[more ...]
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Front and rear power distributors
The BMW 1-Series and the BMW 3-Series have the following power distributors:
1.
Power distributor in the engine compartment: Electronics box
2.
Power distributor in the luggage compartment: Rear fuse block
The fuse block is secured to the vehicle battery by a retaining clip.
The fuse block can only be replaced as a complete unit. Fuses cannot be replaced individually.
The fuse block holds the fuses for the following consumers:
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Valvetronic
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Common rail (fuel injection on diesel)
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Electric auxiliary heater
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Power distributor in junction box
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Intelligent battery sensor
> Only on vehicles with High equipment level, e.g. CCC or M-ASK (CCC: Car Communication Computer, M-
ASK: Multi-audio system controller)
The intelligent battery sensor evaluates the current quality of the battery. The intelligent battery sensor is a part
of the battery negative terminal.
The intelligent battery sensor regularly (cyclically) measures the following values:
•
Battery voltage
•
Charge current
SBT Power supply E81, E82, E87, E90, E91, E92, E93
BMW AG - TIS
22.01.2013 13:30
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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