As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MASTER CAUTION, AIR COND, RT PACK LITE ILLUMINATED ON RECALL PANEL AFTER START CHECKLIST. GROUNDED - YES. HAD RIGHT HAND TEMPERATURE CONTROL VALVE FAIL. IT LOOKS LIKE IT'S BEEN ON AIRCRAFT FOR A VERY LONG TIME. REMOVED AND REPLACED RIGHT HAND TEMPERATURE CONTROL VALVE IAW B737-800 AMM 21-51-10/401.