What was found
FLT#1655, BOS-DCA. (AIRCRAFT PERFORMED AN AIR TURN BACK TO BOS) 'ON DEPARTURE RECEIVED A SLAT / FLAP FAIL EICAS MESSAGE RETURNED TO BOS AND LANDED UNDERWEIGHT; REMOVED AND REPLACED RH OUTBOARD SKEW SLAT SENSOR 3-4 IAW AMM 27-83-01, NO HELP . PER FIM TASK 27-83-00-810-814-A NEXT STEPS ARE WIRING CHECKS. REMOVED AND REPLACED RH SLAT HARNESS (W611) IAW AMM 27-83-07. OPS CHECK GOOD'