Turn Signal Flasher Unit problems of the 1997 Ford Thunderbird

First problem: car door indicator light will not go off even when the doors or tightly shut. Second problem: left turning signal light blinks very fast and the right signal light blinks regularly. Third problem: passenger selt belt keeps getting stuck even after pressing the red button to release. Fourth problem: the squeaking and shaking vibration when driving a speed of 50 or more mph and you begin pressing the brakes is when the sounds and the vibrations begins. Fifth problem: the service light came on and I had it check to the Ford place they stated it was a defect in a box the sits on top of the engine ( I want to say it holds the computer chip) is going bad. At that particular time I did not ask them to do a recall list for me. I really need any information you can give me on this vehicle.