its possible the motors OK and the stepper driver has failed and is only driving one of the 2 coils

a quick web search found a new motor at Newark.com for $378

http://www.newark.com/sanyo-denki-sa...ase/dp/20T1472

103H89222-5241 - Stepper Motor, SANMOTION F2, 1.8° per Step, Circular, Bipolar, 13.2 N-m, 6 A, Two Phase, 0.45 ohm

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photos & details of the X axis stepper driver will be useful



whats the part number of the Y & Z stepper motors ?

Photo & details of the Y & Z stepper drives will be useful
to work out how the motors are being driven
6 wire unipolar or 4 bipolar with 2 wires not being connected

John