Neither of the final stages are connected to any bus so they can't affect sleep mode. Front blower final stage has Terminal 30 (direct battery voltage) supply so it can activate the front blower on it's own and drain the battery. Rear blower final stage is connected to Terminal 15 (voltage supply on ignition switch pos.2) so it can't cause battery drain by itself. Both final stages get separate PWM activation signals from IHKA.

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E39 530dA -02 M-Sport Messing metallic
E53 X5 3.0dA -06 Sport Stratus grey
E70 X5 40d -12 M-Sport Space grey