ABS (trac off) on 2002 Buick Century

When applying the brakes,there is a sudden loss in presure,then the ABS (trac off) lights up on the dash, What component in the ABS system has failed?

2 answers
This is a common problem, there is a service bulletin about it, but $900 later no one has been able to fix mine yet. So I just pulled the fuse for the ABS and drive it that way with no problems.
You need to pull the ABS codes. There a several, then you will know which part of your computer controlled Braking and Traction Control system is defective.