After you notice that the BMW 3 E90 catches fire indicator on the salon filter, you can use a set of peat keys (8 mm) and a replacement filter, reload it yourself. To do this, you must perform a series of steps in the following sequence:
1. Replace the air filter of the passenger compartment which is located on the passenger side of the engine compartment near the thermal shield.
2. Use the end key to unscrew the six bolts of the air filter compartment.
3. Remove the old filter and place a new one. Install the cover and tighten the bolts.
4. Insert the smart key into the ignition switch and press the Start/Stop button of the engine. Wait until the service indicators are down.
5. Press and do not release until the service menu indicator appears, the daytime reset button (located on the dashboard).
6. Switch between the submenu until the "Salon filter" is shown on the dashboard. Press and hold the "BC" button to reset the alert screen.
