Mechanic recently replaced the Rotors and brake pads on my 2003 Cadillac CTS, they noticed they could not rotate the tires while the car was on the lift, afterwards they confirmed the brakes were locked, They bled the brakes,checked the lines (all ok) , checked the master cylinder all ok, disconnected EBCM still locked, removed the new rotors and brakes and put back the old rotors and pads and its now partially locked up, still not drive able, They flushed the entire system and still. The brake pistons push in just fine. This has been ongoing now for 1 week and they are dumbfounded. This shop has been in business for over 35 years and its a mystery, ANy feed back with ideas would be appreciated. Im not a mechanic but im pretty mechanically inclined and they've tried everything i could think of along with there own expertise input. Please HELP!