What was found
DURING TAXI OUT MAIN GEAR STEERING ALERT ON EICAS - FLASHED UP & DISAPPEARED DURING ONE OF FOUR TURNS TO RUNWAY. AFTER LINE UP & TOGA PRESSED - MAIN GEAR STEERING WARNING ANNUNCIATED. REJECTED TAKEOFF & RTB AT 40KTS. EICAS MAIN GEAR STEERING ANNUNCIATED AGAIN DURING ONLY ONE SUBSEQUENT TURN DURING RTB. STATUS MESSAGE REMAINED. REMOVED & REPLACED HARNESS W7244 PER AMM 32-11-30-4 & CMM 32-10-27. PERFORMED BELOW TESTS. ANTISKID/AUTOBRAKE CONTROL SYSTEM-SYS TEST IAW AMM 32-42-00-5, MLG STEERING SYSTEM-FUNCTION TEST IAW AMM 32-53-00-5, PROXIMITY SENSOR ELECTRONICS UNIT-SYS TEST IAW AMM 32-08-00-5, TIRE PRESSURE INDICATION SYS-FUNCTION CHECK IAW AMM 32-49-00-5, & TEST OF TRUCK TILT SENSOR IAW AMM 32-61-03-2.