What was found
FLT#271, LGA-FLL. 'UPON EXITING THE RUNWAY AFTER LANDING, N/W STRG FAULT, AND FAILURE. BROUGHT THE AIRCRAFT TO A STOP, AND RESET A/SKID N/W SW WHICH CLEARED THE FAULT. AFTER SOME TAXIING, N/W STRG FAILED AGAIN AND WE USED DIFFERENTIAL BRAKING TO BRING THE AIRCRAFT TO A SAFE POSITION. FAULT CLEARED BUT L/G SYS DISAGREE MSG REMAINED W/ N/W STEERING AMBER ON WHEEL PAGE; REMOVED AND REPLACED NOSE WHEEL STEERING SERVO CONTROL 6GC IAW AMM: 32-51-51 AND PER TSM 32-51-00-810-826-A. OPS AND LEAK CHECK OK.'