Ford Expedition

I have a 1999 Expedition, 5.4LT automatic, 4 wheel drive. Last week the ABS light started to illuminate after the engine was started. Now, when first started and moved, I get a vibration in the brake pedal as if I am on ice and losing traction, the the ABS light will illuminate and the vibration will cease.
Ted Williams
November 18, 2007.

1: sensor
2: wheel bearing hub
3: wires
One of the sensors giving wrong reading
Have system check for codes and u can also check wires on sensors if damage
Or the ring

Nov 18, 2007.