The BSM B3 integrates several electrical protection and control functions into a single compact unit to simplify wiring and system integration. Its primary roles include:

Providing fused power to the engine and body systems.

While specific internal schematics are often proprietary, the is defined by its external interfaces and pinouts, which are generally consistent across variants.

House-switching relays for critical components like fuel pumps, lighting (including fog lights), and auxiliary systems.

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