[wiswind]

Is the ABS light coming ON?
One thing to check......the fluid level in the master cylinder MUST be right up at the full line.
Even VERY slightly low will cause the BRAKE and/or ABS light to come on.
That would be the FIRST thing that I would check.

If that is not the issue.....you might check the distance between the wheel speed sensor and the exciter ring "teeth".
The exciter ring is the item on the end of the drive shafts that looks like a gear.
There is a sensor that has a wire going to it....if it is not at the correct distance from the teeth of the exciter ring, it can cause the ABS light to come on.
It should not be touching the teeth.......but not be too far way (you can look at the other sensors and compare).

Those are the quick & easy checks.....and hopefully it is the first one.....as it is the easiest.......2nd being fairly easy also.

Of course, if you find that the exciter ring is broken...(teeth missing), then it gets more complicated.