brakes lock up after about 2-3 miles. get hot, smoke both sides. will not move on 2002 Mercury Villager

brake light lamp and brake pads went bad. replaced them. then brakes acted like hard to push. even when u let off gas and didn't hold brakes, brakes stopped car. replaced calipers,rotars, brake lines, now master cylinder, rereplaced brake pads. what causes brakes or wheels to lock up like that even after all those new parts?

Asked by for the 2002 Mercury Villager
could be the wrong master cyl or possible contamination in brake fluid
1 more answer
Loosen brake master cylinder where it bolts to brake booster and see if brakes release. Could have had fluid leak into booster and it could need to be replaced.