It started 3 yrs ago, I had a little meeting w/ a sign. I got the body fixed because they said nothing was wrong with engine. Shortly thereafter, in march 08, the service vehicle soon light would come on then abs& trac off light, almost as if I had a short or something loose. So I have dealt with this ongoing for 2 yrs, My GMC mechanic believes it is a voltage issue with in the car just doesn't know where. So today the service engine soon light comes on and we are driving home and the car instrument panel will light up with all lights and then off and svc eng, svc veh, and brake, abs, and trac off were left on. I pulled into the garage and shut it off but already knew she was not going to start. I tightened battery cables & car started but same old lights still come on. WTF is the problem here with these lights.