Neutral Drift Shift Strategy (Phase 3 Shifts)

NOTE: If after the 5th blocked shift and reversal attempt, if the transfer case position is in the NEUTRAL or other undesired region, shift attempts will continue until a non-NEUTRAL or a desired position is reached.

Phase 3 is a series of shifts whose intent is to escape from an undesired position that has been reached outside of a shift. A perceived drift of the transfer case into a non-target region without the FCM driving the shift motor will initiate a phase 3 shift. Phase 3 will be initiated by any non-target region with the exception of a position greater then encoder_4LO_min or less then encoder_4LOCK_max. Whenever these encoder readings have been seen for defined period of time, Phase 3 shifting will begin.

The shifts in a given Phase 3 shifting event are always in a single-direction, toward the target region from which the drift occurred. These shifts are performed without regard to shift conditions. The timing of each shift should follow the outline of the Phase 1 forward attempts, allowing the shift timer to reach the target. Between each attempt, there is a calibrated delay. After each attempt the shift counter and the Phase 3 max shifts counter will be updated.