ABS Light came on after changing a front wheel bearing?

Hello, Change the passenger side front wheel bearing on my uncles 1999 Mercedes 320 S Class, W220 chassis... The abs light came on after that, I tried turning the wheel all the way right to left then centre the wheel, turn the car off then restart, I read this was supposed to reset it but no luck, when I drive over 15 or 20 MPH an airmatic malfunction come up on the dash and the steering goes heavy...Turn off the car then it will not do that again until I hit the 15/20 mph mark...
I do not understand what I could have done wrong on a simple little thing as changing a bearing, the only difference with the seal at the back where the large ring around it for the sensor to read, one was silver the new one is goldish....
Thanks in advance for any help

Ron
July 2009