As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CONT CAB ZONE TEMP LIGHT ILLUMINATES ON MASTER RECALL. LIGHT EXTINGUISHES ON MASTER CAUTION RESET. GROUNDED - YES. PERFORMED PACK TEMP CONTROL BITE PROCEDURE ON #1 & 2 PACK /ZONE TEMP CONTROLLER. PER B737-800 FIM 21-62. FOUND FAULT ON ZONE TEMP CONTROLLER 2 "FLT DECK TRIM VALVE" PERFORMED "VERIFY" TEST. FAULTS CLEARED.