What was found
FLT 378 FLL-LGA, CREW DECLARED AN EMERGENCY AND AIRCRAFT DIVERTED TO JFK DUE TO GEAR WOULD NOT EXTEND. ATTEMPTED NORMAL LANDING GEAR EXTENSION ON FINAL, CYCLED HANDLE, DID NOT HELP. DIVERTED TO JFK AFTER SUCCESSFUL QRH GRAVITY EXTENSION. PERFORMED TSM TASKS 32-31-00-810-853A & 32-31-00-810-808A. REMOVED & REPLACED RELAYS (53GA) & (48GA) IAW IAW ASM 32-31-05 & 32-31-07. PERFORMED L/G RETRACTION & EXTENSION TEST IAW AMM 32-30-00. NO FAULTS NOTED. LANDING GEAR GROUND CHECK NORMAL.