breaks

Is the rear brakes that are locked up if so perhaps the emergency brake is not releasing. If all brakes are not releasing then the brake master cylinder may not be returning brake fluid to the brake master cylinder but dirty fluid or debris in the system. Try to see if the brakes are locked up front or rear or all four wheels.

I would highly suspect brake fluid contamination - if your brake fluid has been added to and any other fluid besides clean DOT3 Brake fluid has been installed your system, it is contaminated and more then likely all the parts containing rubber products in your system (Master Cylinder, Wheel Cylinders, Calipers, Brake Hoses, ABS Pump) will need to be replaced to make the brakes safe and operational again.