As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT PACK LIGHT ILLUMINATED. PACK SWITCH PLACED OFF IAW QRH. ACFT GROUNDED. ACCOMPLISHED LT AND RT PACK ZONE TEMP CONTROLLER BITE REF FIM 21-62, TASK 801. NO FAULTS LOGGED. RAN LT PACK FOR 40 MINUTES. NO PACK LIGHT NOTED. DUE TO HISTORY IAW SEAM C, R & R A/C MODULE IAW AMM TASK 21-51-65-000-801 AND 21-51-65-400-801. INSTALLATION TEST PASSED IAW SAME. ETOPS SIGNIFICANT SYS VERIFIED.