What was found
LEFT INTAKE INOP CAME ON DURING FLIGHT, SHUT SYSTEM OFF, RESELECTED ON AND LIGHT CAME BACK ON AFTER BETWEEN 15-80 SECONDS. SHUT SYSTEM OFF FOR SEVERAL MINUTES AND TRIED AGAIN, SAME THING HAPPENED. AIRCRAFT RETURNED TO DTW. MAINTENANCE SWAPPED NORMAL AND OVERTEMP SENSORS TO SPARE SENSORS. GROUND RAN AIRCRAFT, ALL CHECKS GOOD.