As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT#1290, ILM-BOS. (AIRCRAFT PERFORMED AN AIR TURN BACK ILM) 'R COWL A/ICE FAIL ON CAUTION ON EICAS IN CRUISE FL370, SELECTED R COWL A/ICE - OFF IAM ECL. CAUTION REMAINED ON EICAS FOR APPROX 3 MINS REPEAT ITEM 5 TM OCCURRENCE; REMOVED & REPLACED UPPER ANTI-ICE CALVE ASSY AND COWL TRANSDUCER IAW APM REF J30-21-01 OPS TEST GOOD.'