As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WE HAD SMOKE OF AN UNKNOWN ORIGIN. REMOVED AND REPLACED COCKPIT (ART) AIR CYCLE MACHINE WITH A REPAIRED UNIT IAW 750 M/M 21-51-00. PRE-LUBED ACM IAW 750M/M 12-10-01 CLEANED COALESCER IAW 750M/M 12-10-01 OPS CHECKED PROVED SATISFACTORY.