It's impossible for your ABS light to come on and there be no code stored in the computer.
Where did you have your computer scanned and what kind of scanner did they scan it with? If you went to AutoZone or O'Riellys, then their scanners aren't capable of reading ABS codes. You'll need a shop with a better scanner to read these.
Also, sometimes a scanner won't be able to retrieve information from the diagnostic link because of your cars connector being faulty. If this is the case, then check the fuse, then the pins inside of the connector and finally the wiring.