As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 2578 - MLS - FOUND LEFT HYDRAULIC LOW PRESS WARNIG LIGHT CAME ON WHEN FLAPS WERE LOWERED. HYDRAULIC PRESSURE REMAINED AT 2,000 PSI. CREW RETURNED TO MAIN BASE, ALTERNATE LANDING LOCATION, DUE TO REPORTED ICING CONDITIONS AND WEATHER AT DESTINATION STATION. HYDRAULIC PRESSURE SWITCH FAILURE. REPLACED LEFT HYDRAULIC PRESSURE LOW SWITCH. (M)