As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON MASTER RECALL AFT CABIN ZONE TEMP LIGHT ILLUMINATED, CONFIRMED. CHECKED, NO HISTORY. NR 1 TEMP CTRLR SHOWS "TRIM VALVE ZONE" ON BIT TEST ONLY. PREV FLT & VERIFY TESTS GOOD. RESET FAULT. FAULT DID NOT RETURN. BITE TESTS NR 1 CTRLR GOOD. REF MM 21 61 00/501.