What was found
ORD - FLT 1063 - EN ROUTE YYZ-ORD, DURING CLIMB, THE GEAR DOOR LIGHT ILLUMINATED. FOLLOWED CHECKLIST, TURNED ON RIGHT ENGINE HYDRAULICS AND LIGHT REMAINED OFF FOR REST OF THE FLIGHT. LANDED ORD WITHOUT INCIDENT. REPLACED SENSOR ON LEFT MAIN LANDING GEAR. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)