What was found
CABIN PRESSURE WARNING IN FLIGHT AT 12,000 FT. BEFORE ABLE TO RUN CHECKLIST WARNING DISAPPEARED. CYCLED BLEEDS. REMOVED FROM SERVICE. INTERROGATED CDS & FOUND FAULTS CPC/OF VALVE DATA FAIL (STATUS) & CP CONTROLLER FAIL (STATUS). PERFORMED Q400 FIM TASKS 21-30-00-810-804 STEPS 1-3.B.(B)(H) & STEP 5. CLOSE OUT. & 21-30-00-810-809 STEP 1-3.B.(4) & STEP 5. CLOSE OUT. FUNCTIONAL TEST OF THE PRESSURIZATION CONTROL IAW Q400 AMM 21-31-00-720-801. FUNCTIONAL TEST GOOD, NO FURTHER DEFECTS NOTED. (CODES CLEARED & DID NOT RETURN). NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.