1992 CADILLAC BROUGHAM Electrical System Problems

I PURCHASED A NEW 1992 4 DOOR CADILLAC BROUGHAM. AT PRESENT THE CAR HAS 45,000 MILES. ALL 4 DRS AUTOMATICALLY LOCK WHEN THE GEAR SHIFT IS ENGAGED. PROBLEM: STARTING AROUND MID-DECEMBER, 2005 AND THROUGH MARCH 30, 2006, ALL 4 DRS AUTOMATICALLY UNLOCKED WHILE THE CAR WAS IN MOTION. THIS HAPPENED ABOUT 4-5 TIMES IN THIS TIME PERIOD. OTHER THAN THE DOORS UNLOCKING, THERE WERE NO OTHER OPERATIONAL PROBLEMS. ON MARCH 31, 2006, ALL 4 DRS UNLOCKED AGAIN. THIS TIME, ABOUT ONE (1) MINUTE AFTER THE DOORS UNLOCKED, THE ENGINE SHUT DOWN LEAVING ME WITH NO POWER BRAKES OR STEERING. TRYING TO MANEUVER A POWERLESS CAR WITH NO FOOT BRAKES AND DIFFICULTY WITH STEERING AMONGST OTHER VEHICULAR TRAFFIC TO A STOP ALONG THE SIDE OF A ONE LANE ROAD IS A SCARY SITUATION! AFTER DOING SO, I NOTICED A LIT DASH LIGHT INDICATING "NO CHARGE." WHEN THE CAR WAS AT A...