As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMBOUT "ZONE TEMP" LIGHT FOR CONT CAB ILLUMINATED. LIGHT EXTINGUISHED PER QRH WITH MASTER CAUTION RESET. GROUNDED - YES. PERFORMED PACK TEMP CONTROLLER BITE REF B737-900 FIM 21-62 TASK 801. FOUND RIGHT CONTROLLER FAULT FLT DECK TRIM VALVE. REPLACED CONTROL CABIN TRIM AIR MODULATING VALVE REF B737-900 AMM 21-61-21/401. OPS CHECK GOOD. NO LEAKS NOTED.