As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER ENGINE START UPON RECALL, AIR COND MASTER CAUTION ILLUMINATED ASSOCIATED WITH THE LEFT PACK OVERHEAD. ACFT GROUNDED. REMOVED THE LT TEMP CONTROL VALVE FOR PACK AFTER ACCOMPLISHING BITE CHECK AND GOT FAULT CODE THIS PACK-TCV IAW AMM 21-51-10-000-801. INSTALLED NEW LT TEMP CONTROL VALVE IAW AMM 21-51-10-400-801.