As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING APPROACH WITH FLAPS AT 1 DEG, THE /LE SLAT ASYM/EICAS MSG AND WARNING LIGHT ABOVE FLAP GAUGE CAME ON. ACCOMPLISHED CHECKLIST IN ATTEMPT TO ELECTRICALLY DRIVE FLAPS TO 20 DEG, BUT NOTHING CHANGED FROM THE 1 DEG POSITION. FLT DIVERTED TO JFK. REPLACED TRAILING EDGE BYPASS VALVE.