I have a 2009 WRX with 46,500 miles, running winter tires on the stock rims and have the original brake pads and rotors still installed. The only thing that has been changed is the usual oil, filter, etc.
A few weeks ago I noticed that my ABS, traction control, and hill-start assist lights lit up when I applied the brakes after first starting my car. It wasn't every time, for instance I could drive a few miles using the brakes now and then without any lights, but then it eventually came on after letting off the brakes. When the lights come on ABS, traction control, and hill-start assist are disabled (obviously), but they work fine until the warning lights come on. I first noticed it after one of the many snowstorms we have had this winter, I was thinking it may just be snow build up near one of the sensors that is throwing something off, but it's remained on even after the snow has cleared and after a car wash.
I did notice a slight squeak when I first apply the brakes initially, but after driving for a bit there aren't any squeaks. So I'm wondering if the brake pads are wearing and that's whats causing the warning lights, or if it's something with one of the speed sensors that may have gotten damaged during the storm. Any thoughts before I bring it to the dealer?