Just bought a C5
Safety Car
Joined: Apr 2007
Posts: 3,640
Likes: 83
From: . New York
I just bought a 99 3 weeks ago and have the same reading. After reading the manual, I realized that when I had the dealer take the tires & wheels off the 2001 on his lot and put them on my car before I bought it, the sensors should also have been swapped. Are yours the original tires & wheels?
Good point. And as Im sure you are aware, you wont be able to train 2001 sensors on a 99
You could obviously replace them with 99 style sensors and be back to normal. May wind up being worth it if you got better wheels in the swap you did 
