As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WITH THE APU RUNNING AND THE NR 2 ENG SHUT DOWN, THE NR 1 ENG WAS SHUT DOWN. THE COCKPIT FILLED WITH SMOKE AND THE CABIN FILLED WITH SMOKE SLIGHTLY. *S/D* FOUND AIR CYCLE MACHINE SEIZED. REPLACED ACM. AIRCRAFT AIR CONDITIONING OPERATES NORMAL.