As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER LANDING LEFT PACK LIGHT ILLUMINATED. AT GATE, LOUD NOISE OBSERVED FROM LEFT PACK. GROUNDED-YES. REPLACED THE LT PACK ACM, LEAK AND OPERATIONS CHECK GOOD, REF B737-900 AMM 21-51-04/401. REPAIR CONFIRMATION SUCCESSFUL, REF B737-900 FIM 21-53 TASK 820 AND 821.