When the cruise control is set while driving, it shuts off automatically. Several times while driving I have notice that the cruise control, and the speed odometer had different reading. 7 miles different in reading, Example when the cruise control is set the odometer reading would be 7 miles faster, I took the vehicle in for service the advisor said he never heard of this problem. He also said that the part needs to be order. I call back a week later to find out about the part, I was told that the part that is needed is order. It is not coming from GM but coming from a third party. I feel that if this part is coming from a third party this is a series problem. And how come there has not been a recall on this part or how come Cadillac has not notify any of there customers. This seems to an ongoing problem with GM (Cadillac) if this part is now a third party part issues. I have had this vehicle for 2 years now and this is the second part that needed to be replace. The first part was the windshield wiper motor. Most people do not recognized the problems with their vehicles because they may not use everything that the vehicle offers. The windshield wipers motor went out when it was raining if I didn't need to turn them on I would not have never known. If I didn't use the cruise control I wouldn't have known. There is no telling what else is not good in the vehicle, but GM (Cadillac) knows but is keeping it hidden from the public and its customers.