What was found
AFTER DESCENT FROM FL 400, MULTIPLE FLAGS ILLUMINATED: ALT LIMI T, ALT DISAGREE, BOTH EEC LIGHTS ALTN, SINGLE CHANNEL SPEED TRIM AND COMPLETE LOSS OF AIRSPEED ON F/O SIDE (ALSO REF PAGE 8742 412). REPLACED RIGHT ADIRU PER AMM 34-21-01 PERFORMED ADIRU OPS TEST PER AMM 34-21-00. REPLACED F/O'S PITOT PROBE(LOW HEAT OUTPUT) PER AMM 34-11-01. LEAK & OPS TEST PER AMM 34-11-00. OK FOR SERVICE REF L/P 8742415 FOR CAT DOWNGRADE. ROTABLE PARTS CHANGE WAS INDICATED - TT 1468629 S/N OFF 01514 UNIT, ADIRU, AI OFF 29-3421-9-0009 1514 ON 29-3421-9-0010 0982.