A fan variable area nozzle includes a flap assembly which varies a fan nozzle exit area through a cam drive ring. A sleeve is mountable on the shaft and carries a multi-pole encoder ring having a radially outwardly facing sensor surface. The second is movable with respect to the developing frame between a first position where the second guide is in continuous with the first guide and a second position where a continuous state of the second guide with the first guide is interrupted.