As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EICAS MSG LE FLAP ASYM FLAP INDICATOR STOPPED BETWEEN 1 AND UP. A/C THEN PERFORMED AIR TURN BACK (ATB) TO FIELD AND LANDED. MTX GROUNDED A/C AND TROUBLESHOT AND FOUND #4 SLAT SENSOR "S279" OUT OF ADJUSTMENT. PLACED SENSOR BACK TO CORRECT INDUCTANCE RANGE, REF B767 AMM 27-88-01. ALL TESTS, FUNCTIONS, AND INDICATIONS NORMAL. A/C REMAINS ETOPS 180. MTX RETURNED A/C TO SERVICE