As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON PUSHBACK ON THE AFTER START, CHECKLIST WE DISCOVERED LEFT PACK LIGHT ON , LIGHT EXTINGUISHED UPON RESET. GROUNDED - YES. REMOVED AND REPLACED LH TEMPERATURE CONTROL VALVE IAW B737-900 AMM 21-51-10-000-801 AND 21-51-10-400-801, ETOPS GROUND FUNCTIONAL CHECK GOOD IAW AMM 21-61-00-700-806-002.