For 1990-2009 cars

1. Disconnect the fresh/recirculate control cable (2) from the clip and door at the blower base.
2. Set the fresh/recirculate lever to the RECIRC position.
3. At the blower case, push the door fully clockwise (rearward) and affix the cable into position.
4. Inspect the fresh/recirculate lever for smooth operation.
5. Ensure the fresh/recirculate lever stops at the proper positions.