"2000 Volkswagen Cabrio: Problems with The Brake Warning Light and ABS Light"

Red 2000 Volkswagen Cabrio Front Left View

I noticed that my 2000 VW Cabrio was having some problems stopping (my foot was going pretty far to the ground, not stopping as quickly as I once was able to do). My brother noticed grooves on all four rotors, so we replaced them, as well as the brakes. I was unable to use my car, as I still had the same problem, plus a brake warning light and ABS light. He then put in ABS rings (which got rid of the ABS light), and played around with the e-brake cable (which removed the brake light). The brake pedal still went to the floor.
Next up were the rear calipers and master brake cylinder. After bleeding the brakes, all four brakes have pressure when the car is not running. However, once the car is turned on, the brakes go down to the floor. We did not attempt to see if they are grabbing on the road or not.
This wasn’t an ongoing problem; my car only seemed to have issues stopping about two weeks before we replaced the brakes and rotors, and even then I only had problems with quick stops and after a rainstorm. Does anybody have any clues what could be wrong? Thanks so much!

Answer: ABS light mean there’s some thing wrong with break system .

1- check break oil
2- check break pads
3- Check break pump and booster .
How ever do not try to drive out ,repeat that do not try to drive out with this light on . Next thing to check is the vacuum booster if it lost vacuum or is loosing vacuum that will make the brake pedal soft and not stop good.