I don't remember much of this dream, but I do remember the end of it.
I was in the car, and I'd been driving around and kept noticing that I was going a bit faster than intended. The passenger in the car kept having a go at me for driving too fast and I just put it down to my own incompetence.
Later on, I was at a junction in a complicated bit of road, with different lanes and side roads going off in all directions. I approached a red light, and tried to stop, but realised that the breaks weren't working. I even tried pulling up the handbrake but that didn't work either. I suddenly realised that it wasn't due my carelessness that I'd been driving a bit fast, but that the brakes has been getting worse and worse all day.
I went through the red light, and luckily there weren't many other cars around. I headed for the closest exit, so that I could drive down a side road and let the car come to a stop.