its the clips on the top of the vent section, there is metal tabs that come out of the dash, they are hard to see as they are under the top of the dash, these tabs fit/clip into the vent section, if you dont get these in right the vents will keep poping out. http://au.toyotaownersclub.com/forums/inde...post&id=490 the gold part in the middle of the pic and the plastic thing directly underneath are what im talking about. hope this helps