As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING AN OPERATIONAL CHECK OF THE INFLATABLE EVACUATION SYSTEM AT THE RT UPPER DECK DOOR ACCORDING MS 23-66-00-040-100 THE RESERVOIR WAS NOT ACTIVATED AND THE SLIDE DID NOT INFLATE. FURTHER INVESTIGATION REVEALED THAT THE PACKBOARD LOCKING PLATE WAS RELEASED DUE TO A BENT MECHANISM. THEREFORE, THE LOCKING PLATE SLIPPED OVER THE LOCKLEVER AND WAS NOT ABLE TO FULLFIL THE ORIGINAL FUNCTION. CHANGED BENT LOCKING PLATE.