As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LAX INFLIGHT T003/15AUG - ON APPROACH WHEN SELECTING FLAPS 20 DEGREES THE MASTER CAUTION LIGHT AND LEADING EDGE SLAT ASYMMETRY EICAS MESSAGE ILLUMINATED. LANDED LAX WITHOUT INCIDENT. BITE CHECK OF PROXIMITY SENSOR ELECTRONIC UNIT FOUND FAULT OF CARDS 001 AND 007. REPLACED CARDS 001 AND 007. SYSTEM GROUND CHECKED NORMAL OPERATION.