What was found
LT MAIN UNSAFE INDICATION, RAN ALT GEAR EXT CHECKLIST. ENDED UP WITH LT MAIN AND NOSE GEAR UNSAFE INDICATION ADN FLAPS WOULD NOT EXTEND BEYOND 20 DEGREES. FLIGHT CREW DID A BLOW DOWN CYCLE OF THE LANDING GEAR TO SEE IF THAT WOULD CLEAR THE INDICATION. IT DID NOT. LT MAIN GEAR ACTUATOR AND DOWN AND LOCKED SWITCH (PN P624007) WERE REPLACED IAW MFG. MAINT CHECKS WERE CARRIED OUT IAW MM, NO FURTHER DEFECTS NOTED. AC WAS RETURNED TO SERVICE. (PA-04-004 CNTRL NR) (K)