Blown Gecko 340

I have damaged one of my G340( terminals 2-3 show 1 ohm resistance)
and I don't know why. This is the 2nd one and after Mariss was kind
enough to repair the first, I redid the wiring completely per the
schematic Tim Goldstein posted.

What is puzzling me is the fact that I had 2 G340s working fine, was
jogging fine, set the speed and acceleration using Mach2, ran some
test gcode rectangles, and had a couple of hours of run time. Yea!

Yesterday went to make a first part, ran the program, moves fine,
wrong zero, stop, try to jog to part zero and the g340 won't come out
of reset. Check resistance of mosfets and trm 2-3 is 1 ohm.

I am looking for reasons for the failure. So far:

Wiring error?
Wiring is the same as the working axis and I did not touch alter it
to my knowlege.

Bad Motor?
I have seen a discussion of bad/shorted windings on steppers causing
damage, could this apply?

Any thoughts would be much appreciated!

Andy