I'm told by someone on a different site : The abs system does a check i believe at around 4mph only the first time you start the car. It sounds like that is what you guys are describing because i wondered the same thing when i first bought the GP. If it only does it once and is when you hit around 4mph right after turning the car on its probably that.
Is there a fuse or a way to disable the ABS ? It would be cool to know one way or the other if it is the ABS doing a check.