I had a problem with the ABS light very frequently coming on. Now I'm extremely technical so during this time I wiggled various wire's, and very frequently when I wiggled the battery terminals I found the ABS light would go off.
Although I do have the radio code, I didn't want to faff about re-inputing it, therefore my permanent cure was giving the battery terminal a few gentle taps with a light hammer and re-tightening the terminal nuts..
Hey don't you knock it, I assure you that this did work for me.
Important Foot Note
If you do decide to remove the battery terminals to clean them make sure you have the Radio / CD code available first.
I'll be surprised if this works twice though, but one never knows.