What was found
WHILE ON A MEDEVAC FLIGHT LT ENG FIRE LIGHT CAME ON, THE INDICATIONS VARIED FROM FLICKERING RAPIDLY TO HOLDING STEADY FOR A BIT. LASTED NO MORE THAN 30 SECONDS, PROBABLY LESS, THEN WENT OUT. VISUALLY INSPECTED LT ENG, WHILE FLYING NOTICED NOTHING ABNORMAL, ALL ENG GAUGES & NOISES WERE NORMAL AS WELL. KEPT ENG RUNNING AS WAS NO OTHER INDICATIONS OR REASONS TO BELIEVE AN ENG FIRE. MX INSPECTED LT ENG FOR EVIDENCE OF FIRE, NO DEFECTS FOUND. TROUBLE SHOT LT ENG FIRE WARNING SYS, NO DEFECTS FOUND. INSPECTED SYS WIRING, AMPLIFIERS & SENSORS. REPLACED LT INBD FIRE DETECTOR. OPERATIONS TESTED GOOD ON GND, OPERATIONS TESTED GOOD ENG RUNNING. PERFORMED OPERATIONAL CHECK FLIGHT WITH NO DEFECTS NOTED.