What was found
LE SLAT ASYM EICAS FOLLOWING SELECTION OF FLAPS 25 FOR LANDING. COMPLIED WITH QRH AFTER GA. EMERGENCY DECLARED. TROUBLESHOT IAW FIM 27-81 FAULT TREE 809. FSEU BITE SHOWS CODE 27-81021. PSEU BITE MESSAGE FAULTS SWITCH S-300. REMOVED AND REPLACED RT OTBD SLAT 12 INBD SWITCH S300 IAW AMM 27-88-01-2. ADJUSTED THE SWITCH TARGET IAW AMM 27-88-01-2. LE SLAT STILL FAULTED. REMOVED AND REPLACED THE PROXIMITY SWITCH ELECTRICAL UNIT IAW AMM 31-70-04-4-99. PSEU TESTED SATISFACTORY. OPERATED SLAT/FLAPS IAW AMM 27-81-00-5. ALL TESTED GOOD. NO FAULTS. ACFT OKAY FOR SERVICE.