Help please-Automatic overdrive, sport mode 2005 sts
 

I have a 2005 STS v8, just purchased it yesterday. I read the book and it says that when you put the car in to drive it should have a [D] for automatic with overdrive on the dash. Then when you move the shifter into [dsc] driver shift control "manual transmission simulated" and do not go up or down, it puts the transmission into sport mode [sD] on the dash. My manual shift works. My issue is that mine is stuck in sport mode [sD] displays on the dash all the time no matter if I have it in drive or dsc. But it does display gear changes when manually shifting. Thanks in advance. I just want regular ol' drive to work.