Do you have a VAGCOM cable? It sounds like the lights might just need to be readjusted.
http://www.ross-tech.com/vag-com/car...alignment.html
It might also be worth looking at the sensor and see if it's obviously been moved. They just clamp onto the lower control arm, and it's possible that they were not reinstalled in exactly the same place. You might be able to see marks in the dirt on the arms that would show where they were originally.
You'l probably want to do the adjustment procedure in any case since any suspension changes could move things around a bit.