As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD - CREW REPORTED HYDRAULIC PRESSURE LOW AND HYDRAULIC QUANTITY ABNORMALLY HIGH ON LEFT SYSTEM. ACCOMPLISHED QRH PROCEDURE. EMERGENCY DECLARED FLIGHT LANDED ORD WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED LEFT HYDRAULIC QUANTITY TRANSMITTER. SYSTEM GROUND CHECK NORMAL OPERATION.