A steering angle sensor assembly is for use with a vehicle having a rotatable steering mechanism. The assembly includes a first rotational indexing member operably couplable to the steering mechanism for rotation therewith. The steering mechanism and the first indexing member are each rotatable through a rotational range including a plurality of revolutions. The first indexing member defines a first rotational axis. A plurality of indexing elements are disposed on the first indexing member and circumscribe the first rotational axis. A first sensing device is positioned to sense the plurality of indexing elements as the first indexing member rotates. The first sensing device outputs a first signal representative of a rotational position of the first rotational indexing member within one of the revolutions. A second rotational indexing member defines a second rotational axis. A reduction gear mechanism operably couples the first and second indexing members. A rotational displacement of the second indexing member is less than a corresponding rotational displacement of the first indexing member. A second sensing device senses a rotational position of said second rotational indexing member and generates a second signal indicative thereof. A logic module receives the first and second signals. The logic module identifies in which one of the revolutions the first indexing member is positioned based upon the second signal and determines the rotational position of the first indexing member within the identified revolution based upon the first signal.