As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MAIN CARGO DOOR INDICATOR LIGHT ILLUMINATED ABOVE FLIGHT LEVEL 390. COMPLETED QRH CHECKLIST AND DESCENDED TO FL350. LIGHT WENT OUT. FOUND AFT LOCK SENSOR LOOSE. SECURED SENSOR AND OPS CHECK OF DOOR INDICATION IAW PRECISION CONTROLS MM 52-50-00. CYCLED DOOR 5 TIMES WITH NO DEFECTS FOUND.