Bad Ground, No Power Assist
In “rare” cases, it has been reported that there is a lack of or no power steering assist on 2012 Buick Regal vehicles equipped with electric power steering. The cause is likely a poor connection at G111 ground (see indicated by red arrows in photo).
On vehicles built prior to Aug. 26, 2011, it has been found that the nut on the ground post could be loose, allowing paint to enter under the nut and negatively impacting the ground connection.
Remove the nut and wire from ground post G111, inspect the base of the ground post and the base of the ground nut. If paint is found, clean the ground post base and replace the M6 nut (GM P/N 11609767) and torque the new nut to 71 in.-lbs.