As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING RANDOM CHECK FOR AIRCRAFT CONDITION, FOUND AIR CONDITIONING TENSIONING PULLEY BEARING DISINTEGRATED. PULLEY WAS HELD IN PLACE BY BELT. ALL BEARING BALLS WERE GONE. ONLY INNER AND OUTER RACE REMAINED. THIS IS SECOND PULLEY TO FAIL ON THIS AIRCRAFT IN 307.8 HOURS. PREVIOUS BEARING TIME UNKNOWN. INSTALLED NEW ASSY.