I have a 2002 Cadillac Deville and a few weeks ago three lights came on at once: Traction Control, ABS and Brake light are all on in my dash. Did something get disconnected? How can I repair this?

Have the code pulled from the computer to find out what set the lights on.the traction control works off of the abs sytem and so if theres a problem its not uncommone for both lights to come on.the brake light and abs lights on at the same time means there is a possible serious problem