What was found
ON SHORT FINAL AFTER MLG SELECTED DOWN, RECEIVED NLG STEERING FAULT, ABORTED APPROACH & FLEW BY TOWER. CYCLED ANTI-SKID & NLG STEERING SWITCH & FAULT CLEARED, DECLARED EMERGENCY & LANDED WITHOUT FURTHER EVENT. MX TROUBLESHOT SYS, BITE CODES INDICATED INTERNAL FAULT IN MLG CONTROL INTERFACE UNIT NR 1. R/R LGCIU NR 1 (D197) IAW AMM, OPS CHECK GOOD. FUNCTIONAL TEST OF LGCIU COULD NOT DUPLICATE REASON FOR REMOVAL, UNIT WAS INSPECTED AND SUBJECTED TO EXTENSIVE TESTING PER CMM, RETURNED TO SERVICE AS NFF.