What was found
LEFT MLG INDICATED UNSAFE, RED LIGHT ONLY, AFTER EXTENSION. HANDLE SEATED, NOSE LANDING RT MAIN INDICATED GREEN. ACCOMPLISHED QRH PROCEDURE & CYCLED LG ON SECOND EXTENSION ON ATTEMPT, LT MLG FULLY EXTENDED, WITH GREEN LIGHT APPROX 10 SECONDS AFTER OTHER TWO LG SHOWED SAFE. R & R MLG ACTUATOR IAW MM.