As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI, AT THE "AFTER START" THE LEFT PACK OFF REMAINED ILLUNMINATED. ACCOMPLISH QRH 2-31. AIRCRAFT RETURNED TO BLOCKS (BTB). MAINTENANCE DEFERRED LT PACK PER MEL 21-51-1-1. MPM 21-51-2 COMPLIED WITH. PLACARDS INSTALLED. MBCB 08-29-25. LP 39197-90/1. AIRCRAFT RETURNED TO SERVICE.