Stepping Motor
WARNING: This page is about a different car, the 2007 Jeep Patriot and 2007 Jeep Compass. However, it is still accessible from the selected car via links, so may be relevant.
If an unexpected condition of the stepping motor is detected by the TCM, the stepping motor coil phases "A" through "D" are all turned OFF to hold the gear ratio used immediately before the unexpected condition occurred.