The only difference on separate rear compartment ventilation is that there is a separate blower motor inside the center console which is controlled with the left wheel on rear console (marked 0 - fan picture vs. 0 - I). On a basic passive version the right wheel only works as a flap control directing or preventing direct flow from main AC housing. On both versions the rear console heat setting wheel works like the stratification flap control on the center face fascia for face vents. When setting is on max red the vents get the same temp like the other vents. When the settings goes towards blue part of the air bypasses heater core so the air is colder than on other vents. That rear console heat setting on the right should guide the rear stratification flap on the main AC unit housing.

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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