As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CHECKING MASTER CAUTION IN CRUISE, AIR CONDITION AND RT PACK LIGHTS ILLUMINATED. HITTING MASTER CAUTION. AGAIN CAUSED BOTH LIGHTS TO GO OUT. ACFT GROUNDED. TESTED RT PACK ZONE CONTROLLER IAW AMM 21-31-00. NO FAULTS FOUND AND NO MAINTENANCE HISTORY WITHIN THE PAST 10 DAYS.