As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFT CABIN ZONE TEMP LIGHT ON RE-SET WITH MASTER CAUTION. ACFT GROUNDED. PERFORMED PACK ZONE TEMP CONTROLLED BITE IAW MM 21-61-00-700-806-002 FOUND AFT CABIN ZONE TRIM MODULATING VALVE FAULT. R & R AFT CABIN ZONE TRIM MOD. VALVE IAW AMM 21-61-21 LEAK CHECK GOOD. PERFORMED OPS TEST FOR ZONE TRIM MOD. VALVE IAW MM 21-61-21-400-801. OPS TEST IS GOOD. OPERATED PACK NO CABIN ZONE TEMP LIGHT. PERFORMED PACK ZONE TEMP CONTROLLER BITE NO FAULTS.