Opel Omega 2.5 TD CD 1996

Good morning forum.
"Problem" story of my omega ....
The computer put me "brake pads" ... well because this is the case ... the front pills should be the problem because they are the ones that have the sneak, because even changing them and disconnecting the cable, the error continues to mark the error.
I do not know why that error continues ... must be the switchboard out? Or what can it be?