As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NUMBER 2 ISOLATION VALVE CAUTION LIGHT ILLUMINATED IN FLIGHT, QUANTITY AND PRESSURE GOOD. REMOVED CANNON PLUG AND CLEANED CONTACTS. BLED NUMBER 2 HYDRAULIC RESERVOIR AND SERVICED. ON THE NEXT FLIGHT, NUMBER 2 ISOLATION VALVE CAUTION LIGHT ILLUMINATED. NUMBER 2 SYSTEM QUANTITY AND PRESSURE REMAINED NORMAL. FOUND CANNON PLUG ON RESERVOIR LEVEL SWITCH INTERMITTENT. REPLACED CANNON PLUG.