Owners of 2011-2012 Buick Regal models (equipped with variable assist power steering) may complain that the steering wheel is difficult to turn at low speeds. The cause may be a variable effort power steering solenoid valve connector that was installed backward/reversed at the rack and pinion connector on the frame.
Using a GDS2 scan tool, navigate to the Power Steering Control Module > Output controls. Then command voltage up on the valve and see if the power steering gets easier to turn. If so, it is likely that the solenoid connector is installed backwards at the in-line connector.
Raise the vehicle on a hoist and look at the in-line connector. Refer to the photos provided here.