As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ZONE TEMP CONT ZONE LIGHT IS ON WITH RECALL. GROUNDED - YES. PERFORMED PZTC BITE PER B737-900 FIM 21-62 TASK 801 #2 CONTROLLER FAULTED CONTROL CABIN TRIM AIR VALVE. PERFORMED FIM 21-62 TASK 832 INITIAL EVALUATION CONTROL CABIN FAULT RESET. OPERATED PACKS FOR 15 MINUTES AND FAULT DID NOT RETURN. REF B737-900 AMM 21-00-00-800-803. PACK IS OPERATING CORRECTLY.