The following article gives detailed instructions on replacing the cabin air filter (microfilter) in a BMW F3x vehicle. Even though we have used a 2014 BMW 320i to perform this installation, this article can be applied to any 2012-2019 3 or 4 series vehicle with minor modifications.
A BMW F3x cabin filter (microfilter) replacement will help restore fresh clean air to the interior of your 3 or 4 series vehicle.
One of the most overcharged dealership maintenance items on a BMW is replacing the cabin air filter, also known as the micro-filter. They are notoriously easy to replace and are very inexpensive to purchase.
The BMW F3x cabin filter does exactly as its name implies; it filters the fresh air being drawn into the interior cabin of your 3 or 4 series car through the heating, ventilation and air-conditioning (HVAC) system. It filters out dust, pollen and other air-borne contaminates as well as noxious odors. It is an extremely important component of your vehicle’s HVAC system and plays an important role in providing a fresh, comfortable, allergen free environment inside your BMW.
The BMW Repair Guide recommends replacing your BMW F3x cabin filter once a year. If you drive in an excessively contaminated environment (like a smog filled city or around heavy road construction) you may want to change it more often.
1. Cabin air filter (required) – There are two different cabin air filters depending on whether you have automatic air conditioning or not. Very simply, if you have a button on your air conditioning controller that says “Auto”…then purchase the automatic air conditioning filter. If you don’t have the “Auto” button on your controls, then purchase the filter for non automatic air conditioning vehicles.
Removing and installing the cabin filter in your 3 or 4 series vehicle is very straightforward. The cabin filter is located inside the car, underneath the dashboard behind the glove box. We recommend putting the passenger seat back as far as it will go to give yourself enough room to remove an install the cabin filter.
- Locate the BMW F3x cabin filter. It is located on the passenger side of the vehicle underneath the glove box.
- Using a 10mm socket wrench, remove the two mounting nuts securing the lower trim panel to the bottom of the dashboard. Grasp the trim panel and pull it loose.
- Disconnect the power accessory outlet and the footwell light. Remove the trim panel from the vehicle.
- Locate the black cabin filter housing under the dashboard. It has a cover on it that is held in place with two torx screws.
- Using a T15 torx bit or torx key, remove the two screws securing the cabin filter cover. Remove the cover from the housing. You can now see the cabin filter.
- Grasp the cabin filter and pull it out of the housing.
- Install a new cabin filter and reassemble the vehicle following the above instructions in reverse. Pay particular attention to the front of the trim panel when reinstalling…the plastic tabs on the trim panel must line up with the slots in the dashboard. Failure to line them up correctly could cause the tabs to break off.