As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
OKC - ON FLIGHT 4184 ,THE PROX SYSTEM 2 FAULT ILLUMINATED FOR THE FORWARD CARGO DOOR. AIRCRAFT RETURNED TO THE FIELD AND ACCOMPLISHED AN UNEVENTFUL LANDING. MAINTENANCE FOUND THE FORWARD CARGO DOOR VENT NOT PROPERLY LATCHED. LATCHED, AND PERFORMED INSPECTION OF AREA, NO DEFECTS NOTED. PERFORMED OPERATIONAL CHECK OFF DOOR, CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE. NO PARTS REPLACED.