What was found
CREW REPORTED, IN CRUISE FLIGHT, THEY GOT AN INDICATION OF CARGO DOOR WARNING LIGHT WITH THE AUDIBLE ALARM. CREW RAN THE BLUE BOOK CHECKLIST FOR THE PROCEDURE. DECLARED AN EMERGENCY AND DIVERTED TO NEAREST AVAILABLE AIRPORT. LIGHT WENT OUT ON FINAL APPROACH, AT 1PSI OR APPROXIMATELY 3000 MSL. MAINTENANCE WAS SENT TO AIRPORT. MAINTENANCE ADJUSTED THE CARGO DOOR ASSIST HANDLE CABLE IAW MM 52-30-01. THE OPS AND RIG CHECKED GOOD. ADDITIONAL TROUBLESHOOTING OF CARGO DOOR FOUND LOCKING CONTROL CABLE OUT OF TOLERANCE. ADJUSTED CABLE IAW MM 52-30-01. RIG AND OPS CHECK WAS GOOD. ACFT WAS RELEASED FOR TEST FLIGHT. THE SUBSEQUENT TEST FLIGHT WAS SATISFACTORY AND ACFT RETURNED TO MAIN BASE.