1998 windstar abs

wife’s van, 1998 ford 2wd windstar abs motor comes on under 5 mph when braking, no abs lite and no codes, all sensor are in spec and OHM out good,all new brakes and tires.

How do you know the ABS motor comes on, and what effect does it have?

This may interest you: http://www.fordwindstarrecall.info/

the motor comes on and and foot brake drops as if you have a wheel slip or lock up, you get the noise from the abs pump and foot pedal shutter . But only under 5 MPH right at the tail end of the stop, over 5mph that all works fine.