What was found
YOW-BOS - FLT 4837 - AFTER DEPARTURE, WHEN THE GEAR WAS SELECTED UP THE HYDRAULIC AUTO MODE CIRCUIT BREAKER POPPED AND WOULD NOT RESET. THE HYDRAULIC PUMP WAS SELECTED TO OVERRIDE AND THE GEAR CAME UP, BOTH THE INTRANSIT LIGHT STAYED ILLUMINATED. GEAR WAS SELECTED NORMAL, AND THE AIRCRAFT RETURNED TO YOW AND LANDED WITHOUT INCIDENT. MAINTENANCE FOUND THE LEFT UPOCK SWITCH TO BE AT FAULT. THEY REPLACED THE LEFT UPLOCK SWITCH, AND FOR PREVENTATIVE REASONS. THE GEAR CONTROL HANDLE P/N D0=404-12-001, S/N 365/06-91. MAINTENANCE THEN PERFORMED GEAR SWINGS AND REQUIRED CHECKS. THE AIRCRAFT WAS THEN RETURNED TO SERVICE. (M)