What was found
PDX-ON FLIGHT NUMBER 2173, ON TAKEOFF WITH BOTH POWER LEVERS AT TAKEOFF POSITION AND BOTH TORQUES APPROX 97 PERCENT, AUTOFEATHER ARM LIGHT FAILED TO ILLUMINATE. DUPLICATED PROBLEM, AUTOFEATHER WOULD NOT ARM OR TEST, REPLACED RELAYS 6121 K-5 & 6121 K-19. OPERATIONALLY TESTED AUTOFEATHER CIRCUITS. AUTOFEATHER ARMED & POWER UPTRIM OPERATED NORMAL. BOTH PROPS WHEN SELECTED AUTOFEATHERED NORMALLY. SYSTEM OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.