Just solved it today. Been away on biz so this was the first chance I had to work on it. Heres what it was, When I received the keys (one owner car) there was no clue to the fact the car had at one point in time a excalibur alarm system. So when I was in the trunk I found a remote for the alarm under the spare tire. This prompted me to look for the aftermarket system. Found it, fuse was removed, installed new fuse. Next I located the "valet button" under the dash. Reprogramed the system and all is good.
Next subject! Who makes the best ORANGE display stereo. The alpine TAPE DECK in the car has green display. That has to go.