As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER START THE CONT CAB ZONE TEMP LIGHT ILLUMINATED AFTER PUSHING RECALL, (ANNUN PANEL) EXTINGUISHED AFTER PUSHING THE MASTER CAUTION LIGHT. GROUNDED - YES. PERFORMED B737-800 FIM 21-62 TASK 801, FOUND TRIM VALVE FLT DECK LIGHT ILLUMINATED ON CONTROLLER, INSPECTED WIRING & CLEANED CANNON PLUG ON ZONE TRIM AIR VALVE. RE-PERFORMED BITE CK NO FAULTS NOTED.