What was found
(CAN) #1 HYDRAULIC PUMP - CYAN L HYD ENGINE PUMP FAIL ILLUMINATED AT FL410. A SHORT PERIOD LATER A CYAN L ENGINE FAULT ILLUMINATED. INITIAL HYDRAULIC SYSTEM SYNOPTIC INDICATED THAT THE RESERVOIR CONTENTS WERE NORMAL. APPROXIMATELY 12-15 MINUTES LATER THE RESERVOIR CONTENTS DEPLETED AND RESULTED IN A TOTAL LEFT HAND HYDRAULICS SYSTEM FAILURE, (WITH THE EXCEPTION OF BRAKES). SPOILERS FAULT EICAS MESSAGES FOLLOWED AS EXPECTED AS IT RELATES TO THE SYSTEM. LANDING GEAR WAS MANUALLY EXTENDED IN RELATION TO L HYDRAULIC SYSTEM FAILURE. EDP REPLACED. (TC# 20190715008)