As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: CATERING REPORTS: GUST LOCK ON 4L DOOR WILL NOT ENGAGE. MAINTENANCE FOUND THE GUST LOCK PIN ROD LOWER NYLON BUSSHING MIGRATED OUT OF PLACE WHICH CAUSED THE MECHANISM TO BIND. MAINTENANCE REPLACED THE LOWER GUIDE AND INSTALLED A NEW NYLON BUSHING PER AMM 52-13-12. A SATISFACTORY OPERATIONAL CHECK WAS ACCOMPLISHED WITH NO ISSUES REPORTED.