What was found
ON TAKEOFF ROLL WITH POWER LEVERS IN THE RATING DETENT, AUTOFEATHER FAILED TO ARM. AUTOFEATHER SWITCHLIGHT WAS DEPRESSED AND "SELECT" WAS ILLUMINATED. TAKEOFF WAS ABORTED ABOVE 60 KTS BUT LESS THAN 80 KTS. RETURNED TO THE GATE. INTERROGATED CDS FOR FAULTS. FOUND FAULT CODE 422 CHANNEL A&B ON NR 1 ENGINE. (UPTRIM A LOGIC FAULT). COMPLIED WITH AUTOFEATHER/ UPTRIM CHECK IAW AMM TASK 61-20-00-710-801. AUTOFEATHER/ UPTRIM TEST FAILED ON NR 1 ENGINE. IAW FIM TASK 61-20-09-810-813. R & R NR 1 PROP ELECTRONIC CONTROL UNIT IAW TASKS 61-20-36-000-801 AND 61-20-36-400-801. ALL OPS TESTS ARE GOOD. NO FAULT CODES INDICATED. OK FOR SERVICE. CHECKED DISCRETE SIGNAL FOR AUTOFEATHER SWITCH IN CDS. SWITCH OPERATES GOOD AND SIGNAL IN CDS IS GOOD. RETURNED TO SERVICE.