I had the same problem last month--after I shattered my front left caliper (which turned the rotor to sea glass). Destroyed the ABS sensor, which made the car's computer assume I was having a braking emergency--spoiler wouldn't come down, spoiler warning light kept flashing like yours, and of course cruise control went out too (not that I needed cruise control as I limped home at 35mph with no front brakes). Clearly you haven't had a catastrophic hardware failure as I did so yes, per other poster, I'd go for the ABS sensor first. Part was ~$120. Good luck.