What was found
HAD TO ABORT TAKEOFF CAUSE AT 77 KTS THE NR 1 + NR 2 BLEED HOT LIGHT + CAUTION CAME ON. RAN NR 1 + NR 2 BLEED HOT CHECKLIST AND THE WENT OFF. DID NOT HAVE TO USE EXCESSIVE BRAKING. REMOVED FROM SERVICE. INTERROGATED CDS FOUND FAULTS: 3003-PACK FCV; 3001-PACK FCV ON LEFT CHANNEL; 3003-PACK FCV; 1007-RNAPRSOV RT CHANNEL FAULTS WOULD NOT CLEAR. REMOVED & REPLACED PACK INLET TEMP SENSOR, IAW Q400 AMM TASKS 21-52-11-000-801 AND 400-801. REMOVED & REPLACED PACK FLOW CONTROL SOV, IAW AMM TASKS 21-52-01-000-801 AND 400-801. ERASED FAULT CODES. RAN BOTH ENGINES FOR 15 MINUTES. C/W PACK FCV OPS TEST. OPS TEST GOOD, NO FAULTS OR CAUTIONS ILLUMINATED. LEAK CHECK C/W, NO LEAKS FOUND. RETURNED TO SERVICE.