I would think your master cylinder is toast. If it was your brake booster then I would think you would still get some braking power, just not much! Still might want to consider the booster since the system was locking up on you before? Lastly, could be air in your line?
Unless your fluid is old it is good. I certainly don't see brake fluid completely crapping out in one day, it degrades slowly over time.
Last edited by tampamark; 01-12-2013 at 07:48 AM.