As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AIR INTERRUPT AND RETURN TO PHL FOR AMBER EICAS"SLAT DRIVE" INDICATION. PERFORMED OVERWEIGHT LGD 393.0LBS 191 FPM. NORMAL TOUCHDOWN. MAINTENANCE REPLACE RIGHT OUTBOARD LEADING EDGE SLAT SKEW DETECTION MECHANISM ASSEMBLY IAW 27-89-03.