As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CARGO DOOR (MAIN) INDICATION LIGHT ON DURING CLIMB FROM CVG. AIRCRAFT RETURNED TO CVG WITHOUT FURTHER INCIDENT. AIRCRAFT WAS GROUNDED BY MAINTENANCE. MAINTENANCE PLACED MCD INDICATION ON DI IAW MEL 52-71-1-2 MBCB 1.30.23 C/W MX PROCEDURES IAW MMP 52-71-1 VERIFIED LATCHED AND LOCKED. AIRCRAFT RETURNED TO SERVICE.