I have had issues with my abs light since I bought it last year. The switch attached to the rear brake lever is very sensitive to dirt or small rocks which will lead to an abs failure for the back brakes and knock out the servo and the two warning lights will flash. Front brakes are not effected. If you look at the rear brake lever from ground level you will see a strip of fairly light metal about 1/2" wide that contacts a bolt as the brake lever is depressed. Usually just moving that metal strip around or blowing some compressed air throught that whole area will clean it out and put you back in business.