How to Change the Cabin Air Filter in a BMW 540i

1. Open the hood and stand in front of your car to look just beneath the windshield wipers.
2. Locate the two cabin air filters, one on each side of the engine, near the passenger and driver's sides of the windshield.
3. Push the side retainer of one of the filters downward to release the cover.
4. Pull the cover upward to expose the rectangular cabin air-filter container.
5. Lift the air filter up and out of the cabin's container.
6. Press the new filter flat into the rectangular air-filter slot, just as the previous filter was positioned. The airflow arrow on the new filter should point downward.
7. Replace the filter cover and listen for a slight clicking sound, indicating that the cover is locked into the side retainer properly.
8. Move to the other side of your hood and repeat steps 1-7 above for the other cabin air filter.
9. Close the hood and enjoy the free-flowing ventilation provided by your fresh cabin air filters.