As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAD - HYDRAULIC SYSTEM A LOW LIGHT ILLUMINATED AND LANDING GEAR DROPPED MANUALLY. EMERGENCY DECLARED, LANDED IAD WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED RESERVOIR PRESSURIZATION MODULE "A" ELECTRIC HYDRAULIC PUMP AND LEFT ENGINE DRIVEN HYDRAULIC PUMP. SYSTEM GROUND CHECK NORMAL OPERATION.