OK, after unplugging the rear sensors it made no difference, when I unplugged the front,
01549 Supply Voltage for Parking-Aid Sensor 29-00 Short To ground error dissapeared, and I got 4 errors saying all 4 front parking sensors are missing.
I measured resistance on all sensors, it was all checking out fine at 10k ohm.
I had no idea what to do, so I took another good working sensor I had, and one by one swapped it with all the sensors in the front bumper, and boom. one of them was faulty even though resistance reading was ok.
1 faulty 12.99 sensor out of 9 i bought is better than 8 working 89.99 geniuine audi sensors any day!