I had this happen to me once when i returned from my honeymoon.
I had left the car in an outdoor Car park in Manchester, UK in the awful month of January.
Once i started the car, the DSC light never went out despite several turning off of the engine and turning on. I filled up the car after an hours drive and it went off.
Strange, and it never happened again.
I would be very interested to see what had caused this.
My car btw was covered completely in Mud, as it had been splashed numerous times by the passing shuttle bus over the two weeks as my car had been parked next to a rather large puddle.
I can only imagin that it was one of the ABS sensors on the car that had become dirty and had just come clean.