So i have a 2010 gmc acadia slt. I just bought it used a few months ago from a dealership, only one owner before me. Recently over the past couple weeks it has started beeping at me while im driving down the road. The parking brake light and traction lights come on then the message center says stabilitrack disabled and then after that it says service brake system. Stays on for a few minutes then goes back to normal... my brakes are fine and nothing seems wrong with my car. It was doing it once and a while but the past few days its been more frequent. I really cant afford to pay a dealership to tell me whats wrong. Any ideas on causes or possible solutions are greatly appreciated.