What was found
ABORTED TWO TAKEOFFS FOR #2 BLEED HOT CAUTION. BLEED CAUTION ILLUMINATED UNDER 80 KNOTS BOTH TIMES AND CAUTION CLEARED AFTER PERFORMING CHECKLISTS. NORMAL BRAKING WAS USED ON BOTH ABORTS. REMOVED FROM SERVICE. C/W Q400 FIM TASK 36-20-00-810-802. PERFORMED OPS TEST OF BLEED AIR SYSTEM REF Q400 AMM TASK 36-11-00-710-802. OPS TEST PASSED, NO FAULTS LOGGED IN CDS AND NO #2 BLEED HOT CAUTION LIGHT. PERFORMED Q400 FIM TASK 21-60-00-810-809. PERFORMED OPS TEST OF THE ECU DIGITAL/AUTOMATIC CHANNELS. REF Q400 AMM TASK 21-61-00-710-802. OPS TEST PASSED. NO FAULTS IN CDS, AND NO CAUTION LIGHTS ILLUMINATED DURING OPS TEST. COULD NOT DUPLICATE. RETURNED TO SERVICE.