What was found
PSC - ON FLIGHT 2101, DURING CLIMB, AUTO FEATHER WAS DESELECTED PER DE CHECKLIST, SELECT PORTION WENT DARK BUT ARM REMAINED ILLUMINATED. DURING THAT DESCENT WHEN POWER LEVELS WERE RETARDED FOR APPROACH, ARM EXTINGUSHED AT APPROX 50 PERCENT TRQ AND REMAINED DARK FOR DURATION OF FLIGHT AT ALL POWER SETTINGS. MAINTENANCE FOUND SWITCH S7 STICKING OPEN BETWEEN C AND NC. CLEANED AND CYCLED NUMEROUS TIMES. ALL OHM CHECKS TEST GOOD. RIGGED S7 SWITCH. AUTO FEATHER/POWER UPTRIM TEST OF PSU GOOD. NO PARTS REPLACED AIRCRAFT RETURNED TO SERVICE.