I had an alternator fail last year and replaced it with an aftermarket one. It never seemed to charge properly and finally failed in 8 months later. During that time several other electrical problems started, specifically the loss of remote control functions. After taking to multiple shops in the Columbia SC area with no resolution, took to a dealer in Charlotte NC. Determined that this model DeVille needed to have an AC/Delco alternator in order to be controlled by the with the powertrain control module. Apparently, not all rebuilt alternators have the correct voltage regulator to interface with the PCU. Changed the alternator to the Delco and sure enough, most of the problems were resolved. However, the remote functions still do not work.