What was found
A/P DISCONNECTED, A/C 10 DEG ROLL TO LEFT WITH A/P ENGAGED WITH NO TURN INTIATED, ROLL FLAG ON EADI, CAPTAINS EADI ROLLS CONTINOUSLY TO LEFT, HEADING ON CAPT'S SIDE DOES NOT MATCH MAG COMPASS OF F/O'S EHSI. AIR RETURN TO DTW. MAINTENANCE REMOVED AND REPLACED NR 1 AHRS COMPUTER P/N 622-6190-113, S/N OFF 2817, S/N ON 241. OPS CHECK GOOD.