1993 Buick Century Owner's Manual - Page 21

2. Push down on the filler panel and the seatback so they lock into a level position. To Raise the Split Second Seatback: 1. Push down on the front edgeof the seatback and pull up the fillerpanel tab. 2. Lift the seatback until it locks in the upright position. Push back and forth on the seatback to be sure it is locked in place.