Air Circulation in Passenger Compartment

[Vasudivan Sunappan <svdivan@xxxxxxxxxxxxx>]

While driving my 97 318i, I always use 'Circulation Mode' for air
circulation which cuts off external air intake. Recently I visited BMW
service center and technical guy told me that in Circulation Mode, the air
intake shutter opens every 12 minutes. Can somebody verify this and duration
the shutter remains open.  

Regards,
SV Divan
Vasudivan Sunappan
Research Fellow
Gintic Institute of Manufacturing Technolgy
71 Nanyang Drive, Singapore 638075
Tel  : (65) 793-8534  Fax : (65) 792-2779
http://www.gintic.gov.sg/epg.html
E-mail : svdivan@domain.elided

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