What was found
WHILE PERFORMING ACCELERATION HEIGHT FLOW AND TURNING OFF AUTOFEATHER, NOTICED BRIEF ILLUMINATION OF MASTER CAUTION PRESS TO RESET SWITCH. NO CHIME, DID NOT NOTICE ANY MASTER CAUTION LIGHTS. NO OTHER ISSUES AND FLIGHT CONTINUED NORMALLY. REMOVED FROM SERVICE. C/W OPERATIONAL TEST OF PROP AUTOFEATHER UPTRIM SYSTEM REF Q400 AMM 61-20-00-710-810 OPS TEST PASS. C/W OPERATIONAL TEST OF AUX PUMP REF Q400 AMM 28-21-31-710-801. OPS TEST PASS. NO ABNORMAL CONDITIONS OR CAUTION LIGHTS. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.