As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE PERFORMING ETOPS PDC FOUND CONTROL CABIN ZONE TEMP LIGHT ILLUMINATED. ABLE TO RESET. ACFT GROUNDED. ACCOMPLISHED PACK/ZONE TEMP CONTROLLER BITE TEST IAW AMM TASK 21-61-00-700-806--002 ON BOTH CONTROLLERS. NO FAULTS NOTED. NO FAULT LAST FLIGHT. OPS CHECK WAS GOOD IAW AMM TASK 21-61-00-700-807-002.