As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CARGO DOOR INDICATION, PRESSURIZATION NORMAL, LIGHT WENT OUT AFTER FLIGHT DESCENDED BELOW FL240. FLIGHT DIVERT TO KATL WHILE AT FL180,A/C LANDED SAFELY AND MTX GROUNDED A/C THEN DEFERRED MAIN CARGO DOOR INDICATION IAW MEL ABX-52-71-1-2 AND RETURNED AC TO SERVICE.