What was found
DTW - FLT 476 - DESCENDING INTO DTW, ALTITUDE ARMED, ALTITUDE DISARMED ITSELF WITHOUT PILOT INTO SHOWING TO 210 KTS AT 12,000 FT. AUTOPILOT WOULD NOT MAINTAIN ALTITUDE DFGC NR 1. CHECKED STP, NO FLIGHT FAULTS LOGGED, PERFORMED A RETURN TO SERVICE BIT CHECK OF BOTH DFGC''S SYSTEM. OPS CHECK GOOD IAW MD-80 MM 27-01-05. (M)