As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER BOTH ENGINES WERE SHUTDOWN, WITH THE APU AND BOTH PACKS RUNNING THE CABIN AND COCKPIT FILLED WITH SMOKE. TROUBLESHOT TO CABIN ACM CAUSING SMOKE. REMOVED OLD ACM AND INSTALLED A REPAIRED ACM IAW 21-00-00. OPS CHECKED AND LEAK CHECKED GOOD.