As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NLG STEERING FAULT, FLT DIVERTED. PER FLT MANUAL, RESET NLG STEERING SWITCH - NO HELP. NO CIRCUIT BREAKERS CYCLED. CFDS SHOWS "NO BSCU 1 DATA". REPLACED BSCU. SYSTEM TESTED GOOD. CAT III TEST CHECKED GOOD. TAXIED AIRCRAFT MAKING NUMEROUS STOPS AND TURNS USING BOTH TILLERS. NO RETURNING FAULTS.