What was found
FLT 3022 - IN CRUISE FLIGHT TO CWA, THE 'SMOKE' LIGHT ILLUMINATED. THE CREW PERFORMED QUICK REFERENCE PROCEDURES. THE CREW DIDN'T NOTE ANY EVIDENCE OF SMOKE OR FIRE. THE AIRCRAFT RETURNED TO DTW. MAINTENANCE WAS UNABLE TO DUPLICATE THE DISCREPANCY. AS A PRECAUTION, THE SMOKE DETECTOR CONTROL AMPLIFIER WAS REPLACED. SYSTEM OPERATED SATISFACTORILY. (Z)