As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT POWERED DOWN ONCE POWERED UP BOTH PACKS WORKED BUT AFTER A FEW SECONDS SMOKE STARTED FILLING THE CABIN. FLIGHT 4263. FOUND RT ACM SEIZED. REMOVED AND REPLACED THE RT ACM, REF CP 33027018 FOR PARTS AND WORK PERFORMED. PERFORMED OPS TEST OF RT PACK REF AMM 21-51-00, OPS TEST, LEAK CHKD GOOD.