What was found
L HYD PRIM PUMP EICAS MSG" EICAS MESSAGE AND LEFT ENGINE DRIVEN PRIMARY PUMP "PRESS LIGHT ILLUMINATED. AICRAFT RETURNED TO BLOCK AND GROUNDED BY MAINTENANCE.REMOVED AND REPLACED #1 ENGINE EDP IAW AMM CHP 29 -11-05. LEAK CHECK GOOD. PERF - PWR CHK AT L ENG HYD PUMP S/O VLV B494 PIN A AND B. NO 28 VDC AT PIN. GOOD 28 VDC AT PIN B W/ FIRE HANDLE UP PER WDM 29-11-11. FOUND DAMAGED WIRE @ P44041, CUT DAMAGED WIRE AND RETERMINATED PER SWPM 20-60-00. VERIFIED L ENG HYD PUMP S/O VLV OPS CHECK GOOD IAW AMM 71-00-00 TEST 3 AND AMM 26-21-01. AIRCRAFT RETURNED TO SERVICE.