2000 Yamaha YFM400FWA(M) Factory Service workshop Manual, Page 359Get this manual
2WD4WD SELECTING SYSTEM
C0NTINUITY INCORRECT
4.On command four-wheel drive switch Refer to "SWITCH INSPECTION"CORRECT
Replace the on command four-wheel drive select switch
5.Gear motor
Check that the shift fork sliding gear is in the 2WD positionDisconnect the gear motor couplerRemove the gear motor from the differential gear caseConnect the battery (12 V) to the gear motor terminals2WD 4WD: Battery (+) terminal BrownWhite terminal Battery () terminal Sky blue terminal 4WD 2WD: Battery (+) terminal Sky blue terminal Battery () terminal BlueBlack terminal 3