What was found
REJECTED TAKEOFF DUE TO NR 1 BLEED HOT CAUTION LIGHT ON TAKEOFF ROLL. NR 2 BLEED HOT CAUTION SHORTLY AFTER CLEARING RUNWAY, RAN CHECKLIST. CAUTION LIGHTS CLEARED. BLEED FLOW SELECTOR WAS IN "MIN" DUCT & CABIN TEMPS APPEARED TO BE NORMAL. TAKEOFF REJECTED BELOW 80 KTS. REMOVED FROM SERVICE. INTERROGATED CDS AND FOUND FAULT 3003-PACK FCV ON BOTH CHANNELS. C/W FIM TASK 36-20-00-810-805. OPERATIONS TEST WAS GOOD AND FAULTS REMAINED EXTINGUISHED. DUE TO HAVING 3003 PREVIOUSLY R & R PACK FLOW CONTROL AND SHUTOFF VALVE, IAW Q400 AMM TASKS 21-52-01-000-801 AND 21-52-01-400-801 STEPS 1-5C. C/W REMAINING STEPS OF Q400 AMM TASK 21-52-01-400-801, LEAK CHECK & OPERATIONS CHECK IS GOOD. NO FAULTS PRESENT IN CDS UNDER ECS SYSTEM. C/W BLEED AIR OPERATIONS TEST, REF Q400 AMM TASK 36-11-00-710-802. OPERATIONS TEST IS GOOD. ALL INDICATIONS ARE NORMAL, NO FURTHER ACTION REQUIRED. AIRCRAFT RETURNED TO SERVICE.