Bosch C3900WS Cabin Air Filter

Bosch Cabin Filter, Activated Carbon C3900WS

Bosch C3900WS is an activated carbon cabin air filter built for BMW applications that need cleaner in-cabin air and odor control. Its 5-layer design adds a carbon layer to capture exhaust-related gases and a protective cover layer for added filtration support.

Key Features

• Activated charcoal filter media for cabin air filtration
• 5-layer construction with an added carbon layer for odor reduction
• Helps absorb ozone, nitrogen oxide, sulfur dioxide, and hydrocarbons
• OEM standard part for direct replacement service
• One filter per vehicle application
• Recommended replacement interval: 12,000 miles

Product Details

The Bosch Cabin Filter, Activated Carbon line is engineered for drivers who want a replacement cabin air filter with multi-layer protection and odor-focused filtration. Part number C3900WS uses activated charcoal media and foam construction to help maintain cleaner airflow through the HVAC system. This Bosch C3900WS cabin air filter is a direct-fit service part for select BMW 5 Series, 6 Series, M5, and M6 models, including 2004-2010 BMW 525i, 530i, 545i, 528i, 535i, 550i, 650i, M5, and M6 applications listed below.

This part cross-references BMW 64319171858 for the same application.

Vehicle Fitment

• Fits 2008-2010 BMW 528i, N/A
• Fits 2009-2010 BMW 528i xDrive, N/A
• Fits 2008-2010 BMW 535i, N/A
• Fits 2009-2010 BMW 535i xDrive, N/A
• Fits 2006-2010 BMW 550i, N/A
• Fits 2006-2010 BMW 650i, N/A
• Fits 2006-2010 BMW M5, N/A
• Fits 2006-2010 BMW M6, N/A
• Fits 2008 BMW 528xi, N/A
• Fits 2008 BMW 535xi, N/A
• Fits 2004-2007 BMW 525i, N/A
• Fits 2006-2007 BMW 525xi, N/A
• Fits 2004-2007 BMW 530i, N/A
• Fits 2006-2007 BMW 530xi, N/A
• Fits 2004-2005 BMW 545i, N/A
• Fits 2004-2005 BMW 645Ci, N/A

Common Issues This Filter Addresses

• Unwanted cabin odors from traffic and exhaust exposure
• Reduced HVAC air cleanliness from a worn filter
• Dust and airborne contaminants entering the passenger compartment
• Declining airflow through a clogged cabin filter
• Need for scheduled maintenance at the 12,000-mile interval

Installation Notes and Tips

Replace the cabin filter at the interval recommended for your service schedule, or sooner if airflow drops or odors increase. Confirm the Bosch C3900WS application against your BMW model and year before ordering, since fitment varies by chassis and engine configuration. For best results, install the filter in the HVAC service location specified for the vehicle and verify airflow direction if marked on the part.

Quality Assurance

Bosch cabin filters are built as OEM standard replacement parts for routine HVAC service. The activated carbon design and multi-layer construction support consistent filtration performance for compatible BMW applications.